/src/postgres/src/backend/catalog/heap.c

Source
/*-------------------------------------------------------------------------
 *
 * heap.c
 *    code to create and destroy POSTGRES heap relations
 *
 * Portions Copyright (c) 1996-2025, PostgreSQL Global Development Group
 * Portions Copyright (c) 1994, Regents of the University of California
 *
 *
 * IDENTIFICATION
 *    src/backend/catalog/heap.c
 *
 *
 * INTERFACE ROUTINES
 *    heap_create()     - Create an uncataloged heap relation
 *    heap_create_with_catalog() - Create a cataloged relation
 *    heap_drop_with_catalog() - Removes named relation from catalogs
 *
 * NOTES
 *    this code taken from access/heap/create.c, which contains
 *    the old heap_create_with_catalog, amcreate, and amdestroy.
 *    those routines will soon call these routines using the function
 *    manager,
 *    just like the poorly named "NewXXX" routines do.  The
 *    "New" routines are all going to die soon, once and for all!
 *    -cim 1/13/91
 *
 *-------------------------------------------------------------------------
 */
#include "postgres.h"

#include "access/genam.h"
#include "access/multixact.h"
#include "access/relation.h"
#include "access/table.h"
#include "access/tableam.h"
#include "catalog/binary_upgrade.h"
#include "catalog/catalog.h"
#include "catalog/heap.h"
#include "catalog/index.h"
#include "catalog/objectaccess.h"
#include "catalog/partition.h"
#include "catalog/pg_am.h"
#include "catalog/pg_attrdef.h"
#include "catalog/pg_collation.h"
#include "catalog/pg_constraint.h"
#include "catalog/pg_foreign_table.h"
#include "catalog/pg_inherits.h"
#include "catalog/pg_namespace.h"
#include "catalog/pg_opclass.h"
#include "catalog/pg_partitioned_table.h"
#include "catalog/pg_statistic.h"
#include "catalog/pg_subscription_rel.h"
#include "catalog/pg_tablespace.h"
#include "catalog/pg_type.h"
#include "catalog/storage.h"
#include "commands/tablecmds.h"
#include "commands/typecmds.h"
#include "common/int.h"
#include "miscadmin.h"
#include "nodes/nodeFuncs.h"
#include "optimizer/optimizer.h"
#include "parser/parse_coerce.h"
#include "parser/parse_collate.h"
#include "parser/parse_expr.h"
#include "parser/parse_relation.h"
#include "parser/parsetree.h"
#include "partitioning/partdesc.h"
#include "pgstat.h"
#include "storage/lmgr.h"
#include "storage/predicate.h"
#include "utils/array.h"
#include "utils/builtins.h"
#include "utils/fmgroids.h"
#include "utils/inval.h"
#include "utils/lsyscache.h"
#include "utils/syscache.h"


/* Potentially set by pg_upgrade_support functions */
Oid     binary_upgrade_next_heap_pg_class_oid = InvalidOid;
Oid     binary_upgrade_next_toast_pg_class_oid = InvalidOid;
RelFileNumber binary_upgrade_next_heap_pg_class_relfilenumber = InvalidRelFileNumber;
RelFileNumber binary_upgrade_next_toast_pg_class_relfilenumber = InvalidRelFileNumber;

static void AddNewRelationTuple(Relation pg_class_desc,
                Relation new_rel_desc,
                Oid new_rel_oid,
                Oid new_type_oid,
                Oid reloftype,
                Oid relowner,
                char relkind,
                TransactionId relfrozenxid,
                TransactionId relminmxid,
                Datum relacl,
                Datum reloptions);
static ObjectAddress AddNewRelationType(const char *typeName,
                    Oid typeNamespace,
                    Oid new_rel_oid,
                    char new_rel_kind,
                    Oid ownerid,
                    Oid new_row_type,
                    Oid new_array_type);
static void RelationRemoveInheritance(Oid relid);
static Oid  StoreRelCheck(Relation rel, const char *ccname, Node *expr,
              bool is_enforced, bool is_validated, bool is_local,
              int16 inhcount, bool is_no_inherit, bool is_internal);
static void StoreConstraints(Relation rel, List *cooked_constraints,
               bool is_internal);
static bool MergeWithExistingConstraint(Relation rel, const char *ccname, Node *expr,
                    bool allow_merge, bool is_local,
                    bool is_enforced,
                    bool is_initially_valid,
                    bool is_no_inherit);
static void SetRelationNumChecks(Relation rel, int numchecks);
static Node *cookConstraint(ParseState *pstate,
              Node *raw_constraint,
              char *relname);


/* ----------------------------------------------------------------
 *        XXX UGLY HARD CODED BADNESS FOLLOWS XXX
 *
 *    these should all be moved to someplace in the lib/catalog
 *    module, if not obliterated first.
 * ----------------------------------------------------------------
 */


/*
 * Note:
 *    Should the system special case these attributes in the future?
 *    Advantage:  consume much less space in the ATTRIBUTE relation.
 *    Disadvantage:  special cases will be all over the place.
 */

/*
 * The initializers below do not include trailing variable length fields,
 * but that's OK - we're never going to reference anything beyond the
 * fixed-size portion of the structure anyway.  Fields that can default
 * to zeroes are also not mentioned.
 */

static const FormData_pg_attribute a1 = {
  .attname = {"ctid"},
  .atttypid = TIDOID,
  .attlen = sizeof(ItemPointerData),
  .attnum = SelfItemPointerAttributeNumber,
  .atttypmod = -1,
  .attbyval = false,
  .attalign = TYPALIGN_SHORT,
  .attstorage = TYPSTORAGE_PLAIN,
  .attnotnull = true,
  .attislocal = true,
};

static const FormData_pg_attribute a2 = {
  .attname = {"xmin"},
  .atttypid = XIDOID,
  .attlen = sizeof(TransactionId),
  .attnum = MinTransactionIdAttributeNumber,
  .atttypmod = -1,
  .attbyval = true,
  .attalign = TYPALIGN_INT,
  .attstorage = TYPSTORAGE_PLAIN,
  .attnotnull = true,
  .attislocal = true,
};

static const FormData_pg_attribute a3 = {
  .attname = {"cmin"},
  .atttypid = CIDOID,
  .attlen = sizeof(CommandId),
  .attnum = MinCommandIdAttributeNumber,
  .atttypmod = -1,
  .attbyval = true,
  .attalign = TYPALIGN_INT,
  .attstorage = TYPSTORAGE_PLAIN,
  .attnotnull = true,
  .attislocal = true,
};

static const FormData_pg_attribute a4 = {
  .attname = {"xmax"},
  .atttypid = XIDOID,
  .attlen = sizeof(TransactionId),
  .attnum = MaxTransactionIdAttributeNumber,
  .atttypmod = -1,
  .attbyval = true,
  .attalign = TYPALIGN_INT,
  .attstorage = TYPSTORAGE_PLAIN,
  .attnotnull = true,
  .attislocal = true,
};

static const FormData_pg_attribute a5 = {
  .attname = {"cmax"},
  .atttypid = CIDOID,
  .attlen = sizeof(CommandId),
  .attnum = MaxCommandIdAttributeNumber,
  .atttypmod = -1,
  .attbyval = true,
  .attalign = TYPALIGN_INT,
  .attstorage = TYPSTORAGE_PLAIN,
  .attnotnull = true,
  .attislocal = true,
};

/*
 * We decided to call this attribute "tableoid" rather than say
 * "classoid" on the basis that in the future there may be more than one
 * table of a particular class/type. In any case table is still the word
 * used in SQL.
 */
static const FormData_pg_attribute a6 = {
  .attname = {"tableoid"},
  .atttypid = OIDOID,
  .attlen = sizeof(Oid),
  .attnum = TableOidAttributeNumber,
  .atttypmod = -1,
  .attbyval = true,
  .attalign = TYPALIGN_INT,
  .attstorage = TYPSTORAGE_PLAIN,
  .attnotnull = true,
  .attislocal = true,
};

static const FormData_pg_attribute *const SysAtt[] = {&a1, &a2, &a3, &a4, &a5, &a6};

/*
 * This function returns a Form_pg_attribute pointer for a system attribute.
 * Note that we elog if the presented attno is invalid, which would only
 * happen if there's a problem upstream.
 */
const FormData_pg_attribute *
SystemAttributeDefinition(AttrNumber attno)
{
  if (attno >= 0 || attno < -(int) lengthof(SysAtt))
    elog(ERROR, "invalid system attribute number %d", attno);
  return SysAtt[-attno - 1];
}

/*
 * If the given name is a system attribute name, return a Form_pg_attribute
 * pointer for a prototype definition.  If not, return NULL.
 */
const FormData_pg_attribute *
SystemAttributeByName(const char *attname)
{
  int     j;

  for (j = 0; j < (int) lengthof(SysAtt); j++)
  {
    const FormData_pg_attribute *att = SysAtt[j];

    if (strcmp(NameStr(att->attname), attname) == 0)
      return att;
  }

  return NULL;
}


/* ----------------------------------------------------------------
 *        XXX END OF UGLY HARD CODED BADNESS XXX
 * ---------------------------------------------------------------- */


/* ----------------------------------------------------------------
 *    heap_create   - Create an uncataloged heap relation
 *
 *    Note API change: the caller must now always provide the OID
 *    to use for the relation.  The relfilenumber may be (and in
 *    the simplest cases is) left unspecified.
 *
 *    create_storage indicates whether or not to create the storage.
 *    However, even if create_storage is true, no storage will be
 *    created if the relkind is one that doesn't have storage.
 *
 *    rel->rd_rel is initialized by RelationBuildLocalRelation,
 *    and is mostly zeroes at return.
 * ----------------------------------------------------------------
 */
Relation
heap_create(const char *relname,
      Oid relnamespace,
      Oid reltablespace,
      Oid relid,
      RelFileNumber relfilenumber,
      Oid accessmtd,
      TupleDesc tupDesc,
      char relkind,
      char relpersistence,
      bool shared_relation,
      bool mapped_relation,
      bool allow_system_table_mods,
      TransactionId *relfrozenxid,
      MultiXactId *relminmxid,
      bool create_storage)
{
  Relation  rel;

  /* The caller must have provided an OID for the relation. */
  Assert(OidIsValid(relid));

  /*
   * Don't allow creating relations in pg_catalog directly, even though it
   * is allowed to move user defined relations there. Semantics with search
   * paths including pg_catalog are too confusing for now.
   *
   * But allow creating indexes on relations in pg_catalog even if
   * allow_system_table_mods = off, upper layers already guarantee it's on a
   * user defined relation, not a system one.
   */
  if (!allow_system_table_mods &&
    ((IsCatalogNamespace(relnamespace) && relkind != RELKIND_INDEX) ||
     IsToastNamespace(relnamespace)) &&
    IsNormalProcessingMode())
    ereport(ERROR,
        (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
         errmsg("permission denied to create \"%s.%s\"",
            get_namespace_name(relnamespace), relname),
         errdetail("System catalog modifications are currently disallowed.")));

  *relfrozenxid = InvalidTransactionId;
  *relminmxid = InvalidMultiXactId;

  /*
   * Force reltablespace to zero if the relation kind does not support
   * tablespaces.  This is mainly just for cleanliness' sake.
   */
  if (!RELKIND_HAS_TABLESPACE(relkind))
    reltablespace = InvalidOid;

  /* Don't create storage for relkinds without physical storage. */
  if (!RELKIND_HAS_STORAGE(relkind))
    create_storage = false;
  else
  {
    /*
     * If relfilenumber is unspecified by the caller then create storage
     * with oid same as relid.
     */
    if (!RelFileNumberIsValid(relfilenumber))
      relfilenumber = relid;
  }

  /*
   * Never allow a pg_class entry to explicitly specify the database's
   * default tablespace in reltablespace; force it to zero instead. This
   * ensures that if the database is cloned with a different default
   * tablespace, the pg_class entry will still match where CREATE DATABASE
   * will put the physically copied relation.
   *
   * Yes, this is a bit of a hack.
   */
  if (reltablespace == MyDatabaseTableSpace)
    reltablespace = InvalidOid;

  /*
   * build the relcache entry.
   */
  rel = RelationBuildLocalRelation(relname,
                   relnamespace,
                   tupDesc,
                   relid,
                   accessmtd,
                   relfilenumber,
                   reltablespace,
                   shared_relation,
                   mapped_relation,
                   relpersistence,
                   relkind);

  /*
   * Have the storage manager create the relation's disk file, if needed.
   *
   * For tables, the AM callback creates both the main and the init fork.
   * For others, only the main fork is created; the other forks will be
   * created on demand.
   */
  if (create_storage)
  {
    if (RELKIND_HAS_TABLE_AM(rel->rd_rel->relkind))
      table_relation_set_new_filelocator(rel, &rel->rd_locator,
                         relpersistence,
                         relfrozenxid, relminmxid);
    else if (RELKIND_HAS_STORAGE(rel->rd_rel->relkind))
      RelationCreateStorage(rel->rd_locator, relpersistence, true);
    else
      Assert(false);
  }

  /*
   * If a tablespace is specified, removal of that tablespace is normally
   * protected by the existence of a physical file; but for relations with
   * no files, add a pg_shdepend entry to account for that.
   */
  if (!create_storage && reltablespace != InvalidOid)
    recordDependencyOnTablespace(RelationRelationId, relid,
                   reltablespace);

  /* ensure that stats are dropped if transaction aborts */
  pgstat_create_relation(rel);

  return rel;
}

/* ----------------------------------------------------------------
 *    heap_create_with_catalog    - Create a cataloged relation
 *
 *    this is done in multiple steps:
 *
 *    1) CheckAttributeNamesTypes() is used to make certain the tuple
 *       descriptor contains a valid set of attribute names and types
 *
 *    2) pg_class is opened and get_relname_relid()
 *       performs a scan to ensure that no relation with the
 *       same name already exists.
 *
 *    3) heap_create() is called to create the new relation on disk.
 *
 *    4) TypeCreate() is called to define a new type corresponding
 *       to the new relation.
 *
 *    5) AddNewRelationTuple() is called to register the
 *       relation in pg_class.
 *
 *    6) AddNewAttributeTuples() is called to register the
 *       new relation's schema in pg_attribute.
 *
 *    7) StoreConstraints() is called     - vadim 08/22/97
 *
 *    8) the relations are closed and the new relation's oid
 *       is returned.
 *
 * ----------------------------------------------------------------
 */

/* --------------------------------
 *    CheckAttributeNamesTypes
 *
 *    this is used to make certain the tuple descriptor contains a
 *    valid set of attribute names and datatypes.  a problem simply
 *    generates ereport(ERROR) which aborts the current transaction.
 *
 *    relkind is the relkind of the relation to be created.
 *    flags controls which datatypes are allowed, cf CheckAttributeType.
 * --------------------------------
 */
void
CheckAttributeNamesTypes(TupleDesc tupdesc, char relkind,
             int flags)
{
  int     i;
  int     j;
  int     natts = tupdesc->natts;

  /* Sanity check on column count */
  if (natts < 0 || natts > MaxHeapAttributeNumber)
    ereport(ERROR,
        (errcode(ERRCODE_TOO_MANY_COLUMNS),
         errmsg("tables can have at most %d columns",
            MaxHeapAttributeNumber)));

  /*
   * first check for collision with system attribute names
   *
   * Skip this for a view or type relation, since those don't have system
   * attributes.
   */
  if (relkind != RELKIND_VIEW && relkind != RELKIND_COMPOSITE_TYPE)
  {
    for (i = 0; i < natts; i++)
    {
      Form_pg_attribute attr = TupleDescAttr(tupdesc, i);

      if (SystemAttributeByName(NameStr(attr->attname)) != NULL)
        ereport(ERROR,
            (errcode(ERRCODE_DUPLICATE_COLUMN),
             errmsg("column name \"%s\" conflicts with a system column name",
                NameStr(attr->attname))));
    }
  }

  /*
   * next check for repeated attribute names
   */
  for (i = 1; i < natts; i++)
  {
    for (j = 0; j < i; j++)
    {
      if (strcmp(NameStr(TupleDescAttr(tupdesc, j)->attname),
             NameStr(TupleDescAttr(tupdesc, i)->attname)) == 0)
        ereport(ERROR,
            (errcode(ERRCODE_DUPLICATE_COLUMN),
             errmsg("column name \"%s\" specified more than once",
                NameStr(TupleDescAttr(tupdesc, j)->attname))));
    }
  }

  /*
   * next check the attribute types
   */
  for (i = 0; i < natts; i++)
  {
    CheckAttributeType(NameStr(TupleDescAttr(tupdesc, i)->attname),
               TupleDescAttr(tupdesc, i)->atttypid,
               TupleDescAttr(tupdesc, i)->attcollation,
               NIL, /* assume we're creating a new rowtype */
               flags | (TupleDescAttr(tupdesc, i)->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL ? CHKATYPE_IS_VIRTUAL : 0));
  }
}

/* --------------------------------
 *    CheckAttributeType
 *
 *    Verify that the proposed datatype of an attribute is legal.
 *    This is needed mainly because there are types (and pseudo-types)
 *    in the catalogs that we do not support as elements of real tuples.
 *    We also check some other properties required of a table column.
 *
 * If the attribute is being proposed for addition to an existing table or
 * composite type, pass a one-element list of the rowtype OID as
 * containing_rowtypes.  When checking a to-be-created rowtype, it's
 * sufficient to pass NIL, because there could not be any recursive reference
 * to a not-yet-existing rowtype.
 *
 * flags is a bitmask controlling which datatypes we allow.  For the most
 * part, pseudo-types are disallowed as attribute types, but there are some
 * exceptions: ANYARRAYOID, RECORDOID, and RECORDARRAYOID can be allowed
 * in some cases.  (This works because values of those type classes are
 * self-identifying to some extent.  However, RECORDOID and RECORDARRAYOID
 * are reliably identifiable only within a session, since the identity info
 * may use a typmod that is only locally assigned.  The caller is expected
 * to know whether these cases are safe.)
 *
 * flags can also control the phrasing of the error messages.  If
 * CHKATYPE_IS_PARTKEY is specified, "attname" should be a partition key
 * column number as text, not a real column name.
 * --------------------------------
 */
void
CheckAttributeType(const char *attname,
           Oid atttypid, Oid attcollation,
           List *containing_rowtypes,
           int flags)
{
  char    att_typtype = get_typtype(atttypid);
  Oid     att_typelem;

  /* since this function recurses, it could be driven to stack overflow */
  check_stack_depth();

  if (att_typtype == TYPTYPE_PSEUDO)
  {
    /*
     * We disallow pseudo-type columns, with the exception of ANYARRAY,
     * RECORD, and RECORD[] when the caller says that those are OK.
     *
     * We don't need to worry about recursive containment for RECORD and
     * RECORD[] because (a) no named composite type should be allowed to
     * contain those, and (b) two "anonymous" record types couldn't be
     * considered to be the same type, so infinite recursion isn't
     * possible.
     */
    if (!((atttypid == ANYARRAYOID && (flags & CHKATYPE_ANYARRAY)) ||
        (atttypid == RECORDOID && (flags & CHKATYPE_ANYRECORD)) ||
        (atttypid == RECORDARRAYOID && (flags & CHKATYPE_ANYRECORD))))
    {
      if (flags & CHKATYPE_IS_PARTKEY)
        ereport(ERROR,
            (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
        /* translator: first %s is an integer not a name */
             errmsg("partition key column %s has pseudo-type %s",
                attname, format_type_be(atttypid))));
      else
        ereport(ERROR,
            (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
             errmsg("column \"%s\" has pseudo-type %s",
                attname, format_type_be(atttypid))));
    }
  }
  else if (att_typtype == TYPTYPE_DOMAIN)
  {
    /*
     * Prevent virtual generated columns from having a domain type.  We
     * would have to enforce domain constraints when columns underlying
     * the generated column change.  This could possibly be implemented,
     * but it's not.
     */
    if (flags & CHKATYPE_IS_VIRTUAL)
      ereport(ERROR,
          errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
          errmsg("virtual generated column \"%s\" cannot have a domain type", attname));

    /*
     * If it's a domain, recurse to check its base type.
     */
    CheckAttributeType(attname, getBaseType(atttypid), attcollation,
               containing_rowtypes,
               flags);
  }
  else if (att_typtype == TYPTYPE_COMPOSITE)
  {
    /*
     * For a composite type, recurse into its attributes.
     */
    Relation  relation;
    TupleDesc tupdesc;
    int     i;

    /*
     * Check for self-containment.  Eventually we might be able to allow
     * this (just return without complaint, if so) but it's not clear how
     * many other places would require anti-recursion defenses before it
     * would be safe to allow tables to contain their own rowtype.
     */
    if (list_member_oid(containing_rowtypes, atttypid))
      ereport(ERROR,
          (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
           errmsg("composite type %s cannot be made a member of itself",
              format_type_be(atttypid))));

    containing_rowtypes = lappend_oid(containing_rowtypes, atttypid);

    relation = relation_open(get_typ_typrelid(atttypid), AccessShareLock);

    tupdesc = RelationGetDescr(relation);

    for (i = 0; i < tupdesc->natts; i++)
    {
      Form_pg_attribute attr = TupleDescAttr(tupdesc, i);

      if (attr->attisdropped)
        continue;
      CheckAttributeType(NameStr(attr->attname),
                 attr->atttypid, attr->attcollation,
                 containing_rowtypes,
                 flags & ~CHKATYPE_IS_PARTKEY);
    }

    relation_close(relation, AccessShareLock);

    containing_rowtypes = list_delete_last(containing_rowtypes);
  }
  else if (att_typtype == TYPTYPE_RANGE)
  {
    /*
     * If it's a range, recurse to check its subtype.
     */
    CheckAttributeType(attname, get_range_subtype(atttypid),
               get_range_collation(atttypid),
               containing_rowtypes,
               flags);
  }
  else if (OidIsValid((att_typelem = get_element_type(atttypid))))
  {
    /*
     * Must recurse into array types, too, in case they are composite.
     */
    CheckAttributeType(attname, att_typelem, attcollation,
               containing_rowtypes,
               flags);
  }

  /*
   * For consistency with check_virtual_generated_security().
   */
  if ((flags & CHKATYPE_IS_VIRTUAL) && atttypid >= FirstUnpinnedObjectId)
    ereport(ERROR,
        errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
        errmsg("virtual generated column \"%s\" cannot have a user-defined type", attname),
        errdetail("Virtual generated columns that make use of user-defined types are not yet supported."));

  /*
   * This might not be strictly invalid per SQL standard, but it is pretty
   * useless, and it cannot be dumped, so we must disallow it.
   */
  if (!OidIsValid(attcollation) && type_is_collatable(atttypid))
  {
    if (flags & CHKATYPE_IS_PARTKEY)
      ereport(ERROR,
          (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
      /* translator: first %s is an integer not a name */
           errmsg("no collation was derived for partition key column %s with collatable type %s",
              attname, format_type_be(atttypid)),
           errhint("Use the COLLATE clause to set the collation explicitly.")));
    else
      ereport(ERROR,
          (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
           errmsg("no collation was derived for column \"%s\" with collatable type %s",
              attname, format_type_be(atttypid)),
           errhint("Use the COLLATE clause to set the collation explicitly.")));
  }
}

/*
 * InsertPgAttributeTuples
 *    Construct and insert a set of tuples in pg_attribute.
 *
 * Caller has already opened and locked pg_attribute.  tupdesc contains the
 * attributes to insert.  tupdesc_extra supplies the values for certain
 * variable-length/nullable pg_attribute fields and must contain the same
 * number of elements as tupdesc or be NULL.  The other variable-length fields
 * of pg_attribute are always initialized to null values.
 *
 * indstate is the index state for CatalogTupleInsertWithInfo.  It can be
 * passed as NULL, in which case we'll fetch the necessary info.  (Don't do
 * this when inserting multiple attributes, because it's a tad more
 * expensive.)
 *
 * new_rel_oid is the relation OID assigned to the attributes inserted.
 * If set to InvalidOid, the relation OID from tupdesc is used instead.
 */
void
InsertPgAttributeTuples(Relation pg_attribute_rel,
            TupleDesc tupdesc,
            Oid new_rel_oid,
            const FormExtraData_pg_attribute tupdesc_extra[],
            CatalogIndexState indstate)
{
  TupleTableSlot **slot;
  TupleDesc td;
  int     nslots;
  int     natts = 0;
  int     slotCount = 0;
  bool    close_index = false;

  td = RelationGetDescr(pg_attribute_rel);

  /* Initialize the number of slots to use */
  nslots = Min(tupdesc->natts,
         (MAX_CATALOG_MULTI_INSERT_BYTES / sizeof(FormData_pg_attribute)));
  slot = palloc(sizeof(TupleTableSlot *) * nslots);
  for (int i = 0; i < nslots; i++)
    slot[i] = MakeSingleTupleTableSlot(td, &TTSOpsHeapTuple);

  while (natts < tupdesc->natts)
  {
    Form_pg_attribute attrs = TupleDescAttr(tupdesc, natts);
    const FormExtraData_pg_attribute *attrs_extra = tupdesc_extra ? &tupdesc_extra[natts] : NULL;

    ExecClearTuple(slot[slotCount]);

    memset(slot[slotCount]->tts_isnull, false,
         slot[slotCount]->tts_tupleDescriptor->natts * sizeof(bool));

    if (new_rel_oid != InvalidOid)
      slot[slotCount]->tts_values[Anum_pg_attribute_attrelid - 1] = ObjectIdGetDatum(new_rel_oid);
    else
      slot[slotCount]->tts_values[Anum_pg_attribute_attrelid - 1] = ObjectIdGetDatum(attrs->attrelid);

    slot[slotCount]->tts_values[Anum_pg_attribute_attname - 1] = NameGetDatum(&attrs->attname);
    slot[slotCount]->tts_values[Anum_pg_attribute_atttypid - 1] = ObjectIdGetDatum(attrs->atttypid);
    slot[slotCount]->tts_values[Anum_pg_attribute_attlen - 1] = Int16GetDatum(attrs->attlen);
    slot[slotCount]->tts_values[Anum_pg_attribute_attnum - 1] = Int16GetDatum(attrs->attnum);
    slot[slotCount]->tts_values[Anum_pg_attribute_atttypmod - 1] = Int32GetDatum(attrs->atttypmod);
    slot[slotCount]->tts_values[Anum_pg_attribute_attndims - 1] = Int16GetDatum(attrs->attndims);
    slot[slotCount]->tts_values[Anum_pg_attribute_attbyval - 1] = BoolGetDatum(attrs->attbyval);
    slot[slotCount]->tts_values[Anum_pg_attribute_attalign - 1] = CharGetDatum(attrs->attalign);
    slot[slotCount]->tts_values[Anum_pg_attribute_attstorage - 1] = CharGetDatum(attrs->attstorage);
    slot[slotCount]->tts_values[Anum_pg_attribute_attcompression - 1] = CharGetDatum(attrs->attcompression);
    slot[slotCount]->tts_values[Anum_pg_attribute_attnotnull - 1] = BoolGetDatum(attrs->attnotnull);
    slot[slotCount]->tts_values[Anum_pg_attribute_atthasdef - 1] = BoolGetDatum(attrs->atthasdef);
    slot[slotCount]->tts_values[Anum_pg_attribute_atthasmissing - 1] = BoolGetDatum(attrs->atthasmissing);
    slot[slotCount]->tts_values[Anum_pg_attribute_attidentity - 1] = CharGetDatum(attrs->attidentity);
    slot[slotCount]->tts_values[Anum_pg_attribute_attgenerated - 1] = CharGetDatum(attrs->attgenerated);
    slot[slotCount]->tts_values[Anum_pg_attribute_attisdropped - 1] = BoolGetDatum(attrs->attisdropped);
    slot[slotCount]->tts_values[Anum_pg_attribute_attislocal - 1] = BoolGetDatum(attrs->attislocal);
    slot[slotCount]->tts_values[Anum_pg_attribute_attinhcount - 1] = Int16GetDatum(attrs->attinhcount);
    slot[slotCount]->tts_values[Anum_pg_attribute_attcollation - 1] = ObjectIdGetDatum(attrs->attcollation);
    if (attrs_extra)
    {
      slot[slotCount]->tts_values[Anum_pg_attribute_attstattarget - 1] = attrs_extra->attstattarget.value;
      slot[slotCount]->tts_isnull[Anum_pg_attribute_attstattarget - 1] = attrs_extra->attstattarget.isnull;

      slot[slotCount]->tts_values[Anum_pg_attribute_attoptions - 1] = attrs_extra->attoptions.value;
      slot[slotCount]->tts_isnull[Anum_pg_attribute_attoptions - 1] = attrs_extra->attoptions.isnull;
    }
    else
    {
      slot[slotCount]->tts_isnull[Anum_pg_attribute_attstattarget - 1] = true;
      slot[slotCount]->tts_isnull[Anum_pg_attribute_attoptions - 1] = true;
    }

    /*
     * The remaining fields are not set for new columns.
     */
    slot[slotCount]->tts_isnull[Anum_pg_attribute_attacl - 1] = true;
    slot[slotCount]->tts_isnull[Anum_pg_attribute_attfdwoptions - 1] = true;
    slot[slotCount]->tts_isnull[Anum_pg_attribute_attmissingval - 1] = true;

    ExecStoreVirtualTuple(slot[slotCount]);
    slotCount++;

    /*
     * If slots are full or the end of processing has been reached, insert
     * a batch of tuples.
     */
    if (slotCount == nslots || natts == tupdesc->natts - 1)
    {
      /* fetch index info only when we know we need it */
      if (!indstate)
      {
        indstate = CatalogOpenIndexes(pg_attribute_rel);
        close_index = true;
      }

      /* insert the new tuples and update the indexes */
      CatalogTuplesMultiInsertWithInfo(pg_attribute_rel, slot, slotCount,
                       indstate);
      slotCount = 0;
    }

    natts++;
  }

  if (close_index)
    CatalogCloseIndexes(indstate);
  for (int i = 0; i < nslots; i++)
    ExecDropSingleTupleTableSlot(slot[i]);
  pfree(slot);
}

/* --------------------------------
 *    AddNewAttributeTuples
 *
 *    this registers the new relation's schema by adding
 *    tuples to pg_attribute.
 * --------------------------------
 */
static void
AddNewAttributeTuples(Oid new_rel_oid,
            TupleDesc tupdesc,
            char relkind)
{
  Relation  rel;
  CatalogIndexState indstate;
  int     natts = tupdesc->natts;
  ObjectAddress myself,
        referenced;

  /*
   * open pg_attribute and its indexes.
   */
  rel = table_open(AttributeRelationId, RowExclusiveLock);

  indstate = CatalogOpenIndexes(rel);

  InsertPgAttributeTuples(rel, tupdesc, new_rel_oid, NULL, indstate);

  /* add dependencies on their datatypes and collations */
  for (int i = 0; i < natts; i++)
  {
    Form_pg_attribute attr = TupleDescAttr(tupdesc, i);

    /* Add dependency info */
    ObjectAddressSubSet(myself, RelationRelationId, new_rel_oid, i + 1);
    ObjectAddressSet(referenced, TypeRelationId, attr->atttypid);
    recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);

    /* The default collation is pinned, so don't bother recording it */
    if (OidIsValid(attr->attcollation) &&
      attr->attcollation != DEFAULT_COLLATION_OID)
    {
      ObjectAddressSet(referenced, CollationRelationId,
               attr->attcollation);
      recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
    }
  }

  /*
   * Next we add the system attributes.  Skip all for a view or type
   * relation.  We don't bother with making datatype dependencies here,
   * since presumably all these types are pinned.
   */
  if (relkind != RELKIND_VIEW && relkind != RELKIND_COMPOSITE_TYPE)
  {
    TupleDesc td;

    td = CreateTupleDesc(lengthof(SysAtt), (FormData_pg_attribute **) &SysAtt);

    InsertPgAttributeTuples(rel, td, new_rel_oid, NULL, indstate);
    FreeTupleDesc(td);
  }

  /*
   * clean up
   */
  CatalogCloseIndexes(indstate);

  table_close(rel, RowExclusiveLock);
}

/* --------------------------------
 *    InsertPgClassTuple
 *
 *    Construct and insert a new tuple in pg_class.
 *
 * Caller has already opened and locked pg_class.
 * Tuple data is taken from new_rel_desc->rd_rel, except for the
 * variable-width fields which are not present in a cached reldesc.
 * relacl and reloptions are passed in Datum form (to avoid having
 * to reference the data types in heap.h).  Pass (Datum) 0 to set them
 * to NULL.
 * --------------------------------
 */
void
InsertPgClassTuple(Relation pg_class_desc,
           Relation new_rel_desc,
           Oid new_rel_oid,
           Datum relacl,
           Datum reloptions)
{
  Form_pg_class rd_rel = new_rel_desc->rd_rel;
  Datum   values[Natts_pg_class];
  bool    nulls[Natts_pg_class];
  HeapTuple tup;

  /* This is a tad tedious, but way cleaner than what we used to do... */
  memset(values, 0, sizeof(values));
  memset(nulls, false, sizeof(nulls));

  values[Anum_pg_class_oid - 1] = ObjectIdGetDatum(new_rel_oid);
  values[Anum_pg_class_relname - 1] = NameGetDatum(&rd_rel->relname);
  values[Anum_pg_class_relnamespace - 1] = ObjectIdGetDatum(rd_rel->relnamespace);
  values[Anum_pg_class_reltype - 1] = ObjectIdGetDatum(rd_rel->reltype);
  values[Anum_pg_class_reloftype - 1] = ObjectIdGetDatum(rd_rel->reloftype);
  values[Anum_pg_class_relowner - 1] = ObjectIdGetDatum(rd_rel->relowner);
  values[Anum_pg_class_relam - 1] = ObjectIdGetDatum(rd_rel->relam);
  values[Anum_pg_class_relfilenode - 1] = ObjectIdGetDatum(rd_rel->relfilenode);
  values[Anum_pg_class_reltablespace - 1] = ObjectIdGetDatum(rd_rel->reltablespace);
  values[Anum_pg_class_relpages - 1] = Int32GetDatum(rd_rel->relpages);
  values[Anum_pg_class_reltuples - 1] = Float4GetDatum(rd_rel->reltuples);
  values[Anum_pg_class_relallvisible - 1] = Int32GetDatum(rd_rel->relallvisible);
  values[Anum_pg_class_relallfrozen - 1] = Int32GetDatum(rd_rel->relallfrozen);
  values[Anum_pg_class_reltoastrelid - 1] = ObjectIdGetDatum(rd_rel->reltoastrelid);
  values[Anum_pg_class_relhasindex - 1] = BoolGetDatum(rd_rel->relhasindex);
  values[Anum_pg_class_relisshared - 1] = BoolGetDatum(rd_rel->relisshared);
  values[Anum_pg_class_relpersistence - 1] = CharGetDatum(rd_rel->relpersistence);
  values[Anum_pg_class_relkind - 1] = CharGetDatum(rd_rel->relkind);
  values[Anum_pg_class_relnatts - 1] = Int16GetDatum(rd_rel->relnatts);
  values[Anum_pg_class_relchecks - 1] = Int16GetDatum(rd_rel->relchecks);
  values[Anum_pg_class_relhasrules - 1] = BoolGetDatum(rd_rel->relhasrules);
  values[Anum_pg_class_relhastriggers - 1] = BoolGetDatum(rd_rel->relhastriggers);
  values[Anum_pg_class_relrowsecurity - 1] = BoolGetDatum(rd_rel->relrowsecurity);
  values[Anum_pg_class_relforcerowsecurity - 1] = BoolGetDatum(rd_rel->relforcerowsecurity);
  values[Anum_pg_class_relhassubclass - 1] = BoolGetDatum(rd_rel->relhassubclass);
  values[Anum_pg_class_relispopulated - 1] = BoolGetDatum(rd_rel->relispopulated);
  values[Anum_pg_class_relreplident - 1] = CharGetDatum(rd_rel->relreplident);
  values[Anum_pg_class_relispartition - 1] = BoolGetDatum(rd_rel->relispartition);
  values[Anum_pg_class_relrewrite - 1] = ObjectIdGetDatum(rd_rel->relrewrite);
  values[Anum_pg_class_relfrozenxid - 1] = TransactionIdGetDatum(rd_rel->relfrozenxid);
  values[Anum_pg_class_relminmxid - 1] = MultiXactIdGetDatum(rd_rel->relminmxid);
  if (relacl != (Datum) 0)
    values[Anum_pg_class_relacl - 1] = relacl;
  else
    nulls[Anum_pg_class_relacl - 1] = true;
  if (reloptions != (Datum) 0)
    values[Anum_pg_class_reloptions - 1] = reloptions;
  else
    nulls[Anum_pg_class_reloptions - 1] = true;

  /* relpartbound is set by updating this tuple, if necessary */
  nulls[Anum_pg_class_relpartbound - 1] = true;

  tup = heap_form_tuple(RelationGetDescr(pg_class_desc), values, nulls);

  /* finally insert the new tuple, update the indexes, and clean up */
  CatalogTupleInsert(pg_class_desc, tup);

  heap_freetuple(tup);
}

/* --------------------------------
 *    AddNewRelationTuple
 *
 *    this registers the new relation in the catalogs by
 *    adding a tuple to pg_class.
 * --------------------------------
 */
static void
AddNewRelationTuple(Relation pg_class_desc,
          Relation new_rel_desc,
          Oid new_rel_oid,
          Oid new_type_oid,
          Oid reloftype,
          Oid relowner,
          char relkind,
          TransactionId relfrozenxid,
          TransactionId relminmxid,
          Datum relacl,
          Datum reloptions)
{
  Form_pg_class new_rel_reltup;

  /*
   * first we update some of the information in our uncataloged relation's
   * relation descriptor.
   */
  new_rel_reltup = new_rel_desc->rd_rel;

  /* The relation is empty */
  new_rel_reltup->relpages = 0;
  new_rel_reltup->reltuples = -1;
  new_rel_reltup->relallvisible = 0;
  new_rel_reltup->relallfrozen = 0;

  /* Sequences always have a known size */
  if (relkind == RELKIND_SEQUENCE)
  {
    new_rel_reltup->relpages = 1;
    new_rel_reltup->reltuples = 1;
  }

  new_rel_reltup->relfrozenxid = relfrozenxid;
  new_rel_reltup->relminmxid = relminmxid;
  new_rel_reltup->relowner = relowner;
  new_rel_reltup->reltype = new_type_oid;
  new_rel_reltup->reloftype = reloftype;

  /* relispartition is always set by updating this tuple later */
  new_rel_reltup->relispartition = false;

  /* fill rd_att's type ID with something sane even if reltype is zero */
  new_rel_desc->rd_att->tdtypeid = new_type_oid ? new_type_oid : RECORDOID;
  new_rel_desc->rd_att->tdtypmod = -1;

  /* Now build and insert the tuple */
  InsertPgClassTuple(pg_class_desc, new_rel_desc, new_rel_oid,
             relacl, reloptions);
}


/* --------------------------------
 *    AddNewRelationType -
 *
 *    define a composite type corresponding to the new relation
 * --------------------------------
 */
static ObjectAddress
AddNewRelationType(const char *typeName,
           Oid typeNamespace,
           Oid new_rel_oid,
           char new_rel_kind,
           Oid ownerid,
           Oid new_row_type,
           Oid new_array_type)
{
  return
    TypeCreate(new_row_type,  /* optional predetermined OID */
           typeName,  /* type name */
           typeNamespace, /* type namespace */
           new_rel_oid, /* relation oid */
           new_rel_kind,  /* relation kind */
           ownerid,   /* owner's ID */
           -1,      /* internal size (varlena) */
           TYPTYPE_COMPOSITE, /* type-type (composite) */
           TYPCATEGORY_COMPOSITE, /* type-category (ditto) */
           false,    /* composite types are never preferred */
           DEFAULT_TYPDELIM, /* default array delimiter */
           F_RECORD_IN, /* input procedure */
           F_RECORD_OUT, /* output procedure */
           F_RECORD_RECV, /* receive procedure */
           F_RECORD_SEND, /* send procedure */
           InvalidOid, /* typmodin procedure - none */
           InvalidOid, /* typmodout procedure - none */
           InvalidOid, /* analyze procedure - default */
           InvalidOid, /* subscript procedure - none */
           InvalidOid, /* array element type - irrelevant */
           false,    /* this is not an array type */
           new_array_type,  /* array type if any */
           InvalidOid, /* domain base type - irrelevant */
           NULL,   /* default value - none */
           NULL,   /* default binary representation */
           false,    /* passed by reference */
           TYPALIGN_DOUBLE, /* alignment - must be the largest! */
           TYPSTORAGE_EXTENDED, /* fully TOASTable */
           -1,      /* typmod */
           0,     /* array dimensions for typBaseType */
           false,    /* Type NOT NULL */
           InvalidOid); /* rowtypes never have a collation */
}

/* --------------------------------
 *    heap_create_with_catalog
 *
 *    creates a new cataloged relation.  see comments above.
 *
 * Arguments:
 *  relname: name to give to new rel
 *  relnamespace: OID of namespace it goes in
 *  reltablespace: OID of tablespace it goes in
 *  relid: OID to assign to new rel, or InvalidOid to select a new OID
 *  reltypeid: OID to assign to rel's rowtype, or InvalidOid to select one
 *  reloftypeid: if a typed table, OID of underlying type; else InvalidOid
 *  ownerid: OID of new rel's owner
 *  accessmtd: OID of new rel's access method
 *  tupdesc: tuple descriptor (source of column definitions)
 *  cooked_constraints: list of precooked check constraints and defaults
 *  relkind: relkind for new rel
 *  relpersistence: rel's persistence status (permanent, temp, or unlogged)
 *  shared_relation: true if it's to be a shared relation
 *  mapped_relation: true if the relation will use the relfilenumber map
 *  oncommit: ON COMMIT marking (only relevant if it's a temp table)
 *  reloptions: reloptions in Datum form, or (Datum) 0 if none
 *  use_user_acl: true if should look for user-defined default permissions;
 *    if false, relacl is always set NULL
 *  allow_system_table_mods: true to allow creation in system namespaces
 *  is_internal: is this a system-generated catalog?
 *  relrewrite: link to original relation during a table rewrite
 *
 * Output parameters:
 *  typaddress: if not null, gets the object address of the new pg_type entry
 *  (this must be null if the relkind is one that doesn't get a pg_type entry)
 *
 * Returns the OID of the new relation
 * --------------------------------
 */
Oid
heap_create_with_catalog(const char *relname,
             Oid relnamespace,
             Oid reltablespace,
             Oid relid,
             Oid reltypeid,
             Oid reloftypeid,
             Oid ownerid,
             Oid accessmtd,
             TupleDesc tupdesc,
             List *cooked_constraints,
             char relkind,
             char relpersistence,
             bool shared_relation,
             bool mapped_relation,
             OnCommitAction oncommit,
             Datum reloptions,
             bool use_user_acl,
             bool allow_system_table_mods,
             bool is_internal,
             Oid relrewrite,
             ObjectAddress *typaddress)
{
  Relation  pg_class_desc;
  Relation  new_rel_desc;
  Acl      *relacl;
  Oid     existing_relid;
  Oid     old_type_oid;
  Oid     new_type_oid;

  /* By default set to InvalidOid unless overridden by binary-upgrade */
  RelFileNumber relfilenumber = InvalidRelFileNumber;
  TransactionId relfrozenxid;
  MultiXactId relminmxid;

  pg_class_desc = table_open(RelationRelationId, RowExclusiveLock);

  /*
   * sanity checks
   */
  Assert(IsNormalProcessingMode() || IsBootstrapProcessingMode());

  /*
   * Validate proposed tupdesc for the desired relkind.  If
   * allow_system_table_mods is on, allow ANYARRAY to be used; this is a
   * hack to allow creating pg_statistic and cloning it during VACUUM FULL.
   */
  CheckAttributeNamesTypes(tupdesc, relkind,
               allow_system_table_mods ? CHKATYPE_ANYARRAY : 0);

  /*
   * This would fail later on anyway, if the relation already exists.  But
   * by catching it here we can emit a nicer error message.
   */
  existing_relid = get_relname_relid(relname, relnamespace);
  if (existing_relid != InvalidOid)
    ereport(ERROR,
        (errcode(ERRCODE_DUPLICATE_TABLE),
         errmsg("relation \"%s\" already exists", relname)));

  /*
   * Since we are going to create a rowtype as well, also check for
   * collision with an existing type name.  If there is one and it's an
   * autogenerated array, we can rename it out of the way; otherwise we can
   * at least give a good error message.
   */
  old_type_oid = GetSysCacheOid2(TYPENAMENSP, Anum_pg_type_oid,
                   CStringGetDatum(relname),
                   ObjectIdGetDatum(relnamespace));
  if (OidIsValid(old_type_oid))
  {
    if (!moveArrayTypeName(old_type_oid, relname, relnamespace))
      ereport(ERROR,
          (errcode(ERRCODE_DUPLICATE_OBJECT),
           errmsg("type \"%s\" already exists", relname),
           errhint("A relation has an associated type of the same name, "
               "so you must use a name that doesn't conflict "
               "with any existing type.")));
  }

  /*
   * Shared relations must be in pg_global (last-ditch check)
   */
  if (shared_relation && reltablespace != GLOBALTABLESPACE_OID)
    elog(ERROR, "shared relations must be placed in pg_global tablespace");

  /*
   * Allocate an OID for the relation, unless we were told what to use.
   *
   * The OID will be the relfilenumber as well, so make sure it doesn't
   * collide with either pg_class OIDs or existing physical files.
   */
  if (!OidIsValid(relid))
  {
    /* Use binary-upgrade override for pg_class.oid and relfilenumber */
    if (IsBinaryUpgrade)
    {
      /*
       * Indexes are not supported here; they use
       * binary_upgrade_next_index_pg_class_oid.
       */
      Assert(relkind != RELKIND_INDEX);
      Assert(relkind != RELKIND_PARTITIONED_INDEX);

      if (relkind == RELKIND_TOASTVALUE)
      {
        /* There might be no TOAST table, so we have to test for it. */
        if (OidIsValid(binary_upgrade_next_toast_pg_class_oid))
        {
          relid = binary_upgrade_next_toast_pg_class_oid;
          binary_upgrade_next_toast_pg_class_oid = InvalidOid;

          if (!RelFileNumberIsValid(binary_upgrade_next_toast_pg_class_relfilenumber))
            ereport(ERROR,
                (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                 errmsg("toast relfilenumber value not set when in binary upgrade mode")));

          relfilenumber = binary_upgrade_next_toast_pg_class_relfilenumber;
          binary_upgrade_next_toast_pg_class_relfilenumber = InvalidRelFileNumber;
        }
      }
      else
      {
        if (!OidIsValid(binary_upgrade_next_heap_pg_class_oid))
          ereport(ERROR,
              (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
               errmsg("pg_class heap OID value not set when in binary upgrade mode")));

        relid = binary_upgrade_next_heap_pg_class_oid;
        binary_upgrade_next_heap_pg_class_oid = InvalidOid;

        if (RELKIND_HAS_STORAGE(relkind))
        {
          if (!RelFileNumberIsValid(binary_upgrade_next_heap_pg_class_relfilenumber))
            ereport(ERROR,
                (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                 errmsg("relfilenumber value not set when in binary upgrade mode")));

          relfilenumber = binary_upgrade_next_heap_pg_class_relfilenumber;
          binary_upgrade_next_heap_pg_class_relfilenumber = InvalidRelFileNumber;
        }
      }
    }

    if (!OidIsValid(relid))
      relid = GetNewRelFileNumber(reltablespace, pg_class_desc,
                    relpersistence);
  }

  /*
   * Other sessions' catalog scans can't find this until we commit.  Hence,
   * it doesn't hurt to hold AccessExclusiveLock.  Do it here so callers
   * can't accidentally vary in their lock mode or acquisition timing.
   */
  LockRelationOid(relid, AccessExclusiveLock);

  /*
   * Determine the relation's initial permissions.
   */
  if (use_user_acl)
  {
    switch (relkind)
    {
      case RELKIND_RELATION:
      case RELKIND_VIEW:
      case RELKIND_MATVIEW:
      case RELKIND_FOREIGN_TABLE:
      case RELKIND_PARTITIONED_TABLE:
        relacl = get_user_default_acl(OBJECT_TABLE, ownerid,
                        relnamespace);
        break;
      case RELKIND_SEQUENCE:
        relacl = get_user_default_acl(OBJECT_SEQUENCE, ownerid,
                        relnamespace);
        break;
      default:
        relacl = NULL;
        break;
    }
  }
  else
    relacl = NULL;

  /*
   * Create the relcache entry (mostly dummy at this point) and the physical
   * disk file.  (If we fail further down, it's the smgr's responsibility to
   * remove the disk file again.)
   *
   * NB: Note that passing create_storage = true is correct even for binary
   * upgrade.  The storage we create here will be replaced later, but we
   * need to have something on disk in the meanwhile.
   */
  new_rel_desc = heap_create(relname,
                 relnamespace,
                 reltablespace,
                 relid,
                 relfilenumber,
                 accessmtd,
                 tupdesc,
                 relkind,
                 relpersistence,
                 shared_relation,
                 mapped_relation,
                 allow_system_table_mods,
                 &relfrozenxid,
                 &relminmxid,
                 true);

  Assert(relid == RelationGetRelid(new_rel_desc));

  new_rel_desc->rd_rel->relrewrite = relrewrite;

  /*
   * Decide whether to create a pg_type entry for the relation's rowtype.
   * These types are made except where the use of a relation as such is an
   * implementation detail: toast tables, sequences and indexes.
   */
  if (!(relkind == RELKIND_SEQUENCE ||
      relkind == RELKIND_TOASTVALUE ||
      relkind == RELKIND_INDEX ||
      relkind == RELKIND_PARTITIONED_INDEX))
  {
    Oid     new_array_oid;
    ObjectAddress new_type_addr;
    char     *relarrayname;

    /*
     * We'll make an array over the composite type, too.  For largely
     * historical reasons, the array type's OID is assigned first.
     */
    new_array_oid = AssignTypeArrayOid();

    /*
     * Make the pg_type entry for the composite type.  The OID of the
     * composite type can be preselected by the caller, but if reltypeid
     * is InvalidOid, we'll generate a new OID for it.
     *
     * NOTE: we could get a unique-index failure here, in case someone
     * else is creating the same type name in parallel but hadn't
     * committed yet when we checked for a duplicate name above.
     */
    new_type_addr = AddNewRelationType(relname,
                       relnamespace,
                       relid,
                       relkind,
                       ownerid,
                       reltypeid,
                       new_array_oid);
    new_type_oid = new_type_addr.objectId;
    if (typaddress)
      *typaddress = new_type_addr;

    /* Now create the array type. */
    relarrayname = makeArrayTypeName(relname, relnamespace);

    TypeCreate(new_array_oid, /* force the type's OID to this */
           relarrayname,  /* Array type name */
           relnamespace,  /* Same namespace as parent */
           InvalidOid, /* Not composite, no relationOid */
           0,     /* relkind, also N/A here */
           ownerid,   /* owner's ID */
           -1,      /* Internal size (varlena) */
           TYPTYPE_BASE, /* Not composite - typelem is */
           TYPCATEGORY_ARRAY, /* type-category (array) */
           false,    /* array types are never preferred */
           DEFAULT_TYPDELIM, /* default array delimiter */
           F_ARRAY_IN, /* array input proc */
           F_ARRAY_OUT, /* array output proc */
           F_ARRAY_RECV, /* array recv (bin) proc */
           F_ARRAY_SEND, /* array send (bin) proc */
           InvalidOid, /* typmodin procedure - none */
           InvalidOid, /* typmodout procedure - none */
           F_ARRAY_TYPANALYZE, /* array analyze procedure */
           F_ARRAY_SUBSCRIPT_HANDLER, /* array subscript procedure */
           new_type_oid,  /* array element type - the rowtype */
           true,   /* yes, this is an array type */
           InvalidOid, /* this has no array type */
           InvalidOid, /* domain base type - irrelevant */
           NULL,   /* default value - none */
           NULL,   /* default binary representation */
           false,    /* passed by reference */
           TYPALIGN_DOUBLE, /* alignment - must be the largest! */
           TYPSTORAGE_EXTENDED, /* fully TOASTable */
           -1,      /* typmod */
           0,     /* array dimensions for typBaseType */
           false,    /* Type NOT NULL */
           InvalidOid); /* rowtypes never have a collation */

    pfree(relarrayname);
  }
  else
  {
    /* Caller should not be expecting a type to be created. */
    Assert(reltypeid == InvalidOid);
    Assert(typaddress == NULL);

    new_type_oid = InvalidOid;
  }

  /*
   * now create an entry in pg_class for the relation.
   *
   * NOTE: we could get a unique-index failure here, in case someone else is
   * creating the same relation name in parallel but hadn't committed yet
   * when we checked for a duplicate name above.
   */
  AddNewRelationTuple(pg_class_desc,
            new_rel_desc,
            relid,
            new_type_oid,
            reloftypeid,
            ownerid,
            relkind,
            relfrozenxid,
            relminmxid,
            PointerGetDatum(relacl),
            reloptions);

  /*
   * now add tuples to pg_attribute for the attributes in our new relation.
   */
  AddNewAttributeTuples(relid, new_rel_desc->rd_att, relkind);

  /*
   * Make a dependency link to force the relation to be deleted if its
   * namespace is.  Also make a dependency link to its owner, as well as
   * dependencies for any roles mentioned in the default ACL.
   *
   * For composite types, these dependencies are tracked for the pg_type
   * entry, so we needn't record them here.  Likewise, TOAST tables don't
   * need a namespace dependency (they live in a pinned namespace) nor an
   * owner dependency (they depend indirectly through the parent table), nor
   * should they have any ACL entries.  The same applies for extension
   * dependencies.
   *
   * Also, skip this in bootstrap mode, since we don't make dependencies
   * while bootstrapping.
   */
  if (relkind != RELKIND_COMPOSITE_TYPE &&
    relkind != RELKIND_TOASTVALUE &&
    !IsBootstrapProcessingMode())
  {
    ObjectAddress myself,
          referenced;
    ObjectAddresses *addrs;

    ObjectAddressSet(myself, RelationRelationId, relid);

    recordDependencyOnOwner(RelationRelationId, relid, ownerid);

    recordDependencyOnNewAcl(RelationRelationId, relid, 0, ownerid, relacl);

    recordDependencyOnCurrentExtension(&myself, false);

    addrs = new_object_addresses();

    ObjectAddressSet(referenced, NamespaceRelationId, relnamespace);
    add_exact_object_address(&referenced, addrs);

    if (reloftypeid)
    {
      ObjectAddressSet(referenced, TypeRelationId, reloftypeid);
      add_exact_object_address(&referenced, addrs);
    }

    /*
     * Make a dependency link to force the relation to be deleted if its
     * access method is.
     *
     * No need to add an explicit dependency for the toast table, as the
     * main table depends on it.  Partitioned tables may not have an
     * access method set.
     */
    if ((RELKIND_HAS_TABLE_AM(relkind) && relkind != RELKIND_TOASTVALUE) ||
      (relkind == RELKIND_PARTITIONED_TABLE && OidIsValid(accessmtd)))
    {
      ObjectAddressSet(referenced, AccessMethodRelationId, accessmtd);
      add_exact_object_address(&referenced, addrs);
    }

    record_object_address_dependencies(&myself, addrs, DEPENDENCY_NORMAL);
    free_object_addresses(addrs);
  }

  /* Post creation hook for new relation */
  InvokeObjectPostCreateHookArg(RelationRelationId, relid, 0, is_internal);

  /*
   * Store any supplied CHECK constraints and defaults.
   *
   * NB: this may do a CommandCounterIncrement and rebuild the relcache
   * entry, so the relation must be valid and self-consistent at this point.
   * In particular, there are not yet constraints and defaults anywhere.
   */
  StoreConstraints(new_rel_desc, cooked_constraints, is_internal);

  /*
   * If there's a special on-commit action, remember it
   */
  if (oncommit != ONCOMMIT_NOOP)
    register_on_commit_action(relid, oncommit);

  /*
   * ok, the relation has been cataloged, so close our relations and return
   * the OID of the newly created relation.
   */
  table_close(new_rel_desc, NoLock);  /* do not unlock till end of xact */
  table_close(pg_class_desc, RowExclusiveLock);

  return relid;
}

/*
 *    RelationRemoveInheritance
 *
 * Formerly, this routine checked for child relations and aborted the
 * deletion if any were found.  Now we rely on the dependency mechanism
 * to check for or delete child relations.  By the time we get here,
 * there are no children and we need only remove any pg_inherits rows
 * linking this relation to its parent(s).
 */
static void
RelationRemoveInheritance(Oid relid)
{
  Relation  catalogRelation;
  SysScanDesc scan;
  ScanKeyData key;
  HeapTuple tuple;

  catalogRelation = table_open(InheritsRelationId, RowExclusiveLock);

  ScanKeyInit(&key,
        Anum_pg_inherits_inhrelid,
        BTEqualStrategyNumber, F_OIDEQ,
        ObjectIdGetDatum(relid));

  scan = systable_beginscan(catalogRelation, InheritsRelidSeqnoIndexId, true,
                NULL, 1, &key);

  while (HeapTupleIsValid(tuple = systable_getnext(scan)))
    CatalogTupleDelete(catalogRelation, &tuple->t_self);

  systable_endscan(scan);
  table_close(catalogRelation, RowExclusiveLock);
}

/*
 *    DeleteRelationTuple
 *
 * Remove pg_class row for the given relid.
 *
 * Note: this is shared by relation deletion and index deletion.  It's
 * not intended for use anyplace else.
 */
void
DeleteRelationTuple(Oid relid)
{
  Relation  pg_class_desc;
  HeapTuple tup;

  /* Grab an appropriate lock on the pg_class relation */
  pg_class_desc = table_open(RelationRelationId, RowExclusiveLock);

  tup = SearchSysCache1(RELOID, ObjectIdGetDatum(relid));
  if (!HeapTupleIsValid(tup))
    elog(ERROR, "cache lookup failed for relation %u", relid);

  /* delete the relation tuple from pg_class, and finish up */
  CatalogTupleDelete(pg_class_desc, &tup->t_self);

  ReleaseSysCache(tup);

  table_close(pg_class_desc, RowExclusiveLock);
}

/*
 *    DeleteAttributeTuples
 *
 * Remove pg_attribute rows for the given relid.
 *
 * Note: this is shared by relation deletion and index deletion.  It's
 * not intended for use anyplace else.
 */
void
DeleteAttributeTuples(Oid relid)
{
  Relation  attrel;
  SysScanDesc scan;
  ScanKeyData key[1];
  HeapTuple atttup;

  /* Grab an appropriate lock on the pg_attribute relation */
  attrel = table_open(AttributeRelationId, RowExclusiveLock);

  /* Use the index to scan only attributes of the target relation */
  ScanKeyInit(&key[0],
        Anum_pg_attribute_attrelid,
        BTEqualStrategyNumber, F_OIDEQ,
        ObjectIdGetDatum(relid));

  scan = systable_beginscan(attrel, AttributeRelidNumIndexId, true,
                NULL, 1, key);

  /* Delete all the matching tuples */
  while ((atttup = systable_getnext(scan)) != NULL)
    CatalogTupleDelete(attrel, &atttup->t_self);

  /* Clean up after the scan */
  systable_endscan(scan);
  table_close(attrel, RowExclusiveLock);
}

/*
 *    DeleteSystemAttributeTuples
 *
 * Remove pg_attribute rows for system columns of the given relid.
 *
 * Note: this is only used when converting a table to a view.  Views don't
 * have system columns, so we should remove them from pg_attribute.
 */
void
DeleteSystemAttributeTuples(Oid relid)
{
  Relation  attrel;
  SysScanDesc scan;
  ScanKeyData key[2];
  HeapTuple atttup;

  /* Grab an appropriate lock on the pg_attribute relation */
  attrel = table_open(AttributeRelationId, RowExclusiveLock);

  /* Use the index to scan only system attributes of the target relation */
  ScanKeyInit(&key[0],
        Anum_pg_attribute_attrelid,
        BTEqualStrategyNumber, F_OIDEQ,
        ObjectIdGetDatum(relid));
  ScanKeyInit(&key[1],
        Anum_pg_attribute_attnum,
        BTLessEqualStrategyNumber, F_INT2LE,
        Int16GetDatum(0));

  scan = systable_beginscan(attrel, AttributeRelidNumIndexId, true,
                NULL, 2, key);

  /* Delete all the matching tuples */
  while ((atttup = systable_getnext(scan)) != NULL)
    CatalogTupleDelete(attrel, &atttup->t_self);

  /* Clean up after the scan */
  systable_endscan(scan);
  table_close(attrel, RowExclusiveLock);
}

/*
 *    RemoveAttributeById
 *
 * This is the guts of ALTER TABLE DROP COLUMN: actually mark the attribute
 * deleted in pg_attribute.  We also remove pg_statistic entries for it.
 * (Everything else needed, such as getting rid of any pg_attrdef entry,
 * is handled by dependency.c.)
 */
void
RemoveAttributeById(Oid relid, AttrNumber attnum)
{
  Relation  rel;
  Relation  attr_rel;
  HeapTuple tuple;
  Form_pg_attribute attStruct;
  char    newattname[NAMEDATALEN];
  Datum   valuesAtt[Natts_pg_attribute] = {0};
  bool    nullsAtt[Natts_pg_attribute] = {0};
  bool    replacesAtt[Natts_pg_attribute] = {0};

  /*
   * Grab an exclusive lock on the target table, which we will NOT release
   * until end of transaction.  (In the simple case where we are directly
   * dropping this column, ATExecDropColumn already did this ... but when
   * cascading from a drop of some other object, we may not have any lock.)
   */
  rel = relation_open(relid, AccessExclusiveLock);

  attr_rel = table_open(AttributeRelationId, RowExclusiveLock);

  tuple = SearchSysCacheCopy2(ATTNUM,
                ObjectIdGetDatum(relid),
                Int16GetDatum(attnum));
  if (!HeapTupleIsValid(tuple))  /* shouldn't happen */
    elog(ERROR, "cache lookup failed for attribute %d of relation %u",
       attnum, relid);
  attStruct = (Form_pg_attribute) GETSTRUCT(tuple);

  /* Mark the attribute as dropped */
  attStruct->attisdropped = true;

  /*
   * Set the type OID to invalid.  A dropped attribute's type link cannot be
   * relied on (once the attribute is dropped, the type might be too).
   * Fortunately we do not need the type row --- the only really essential
   * information is the type's typlen and typalign, which are preserved in
   * the attribute's attlen and attalign.  We set atttypid to zero here as a
   * means of catching code that incorrectly expects it to be valid.
   */
  attStruct->atttypid = InvalidOid;

  /* Remove any not-null constraint the column may have */
  attStruct->attnotnull = false;

  /* Unset this so no one tries to look up the generation expression */
  attStruct->attgenerated = '\0';

  /*
   * Change the column name to something that isn't likely to conflict
   */
  snprintf(newattname, sizeof(newattname),
       "........pg.dropped.%d........", attnum);
  namestrcpy(&(attStruct->attname), newattname);

  /* Clear the missing value */
  attStruct->atthasmissing = false;
  nullsAtt[Anum_pg_attribute_attmissingval - 1] = true;
  replacesAtt[Anum_pg_attribute_attmissingval - 1] = true;

  /*
   * Clear the other nullable fields.  This saves some space in pg_attribute
   * and removes no longer useful information.
   */
  nullsAtt[Anum_pg_attribute_attstattarget - 1] = true;
  replacesAtt[Anum_pg_attribute_attstattarget - 1] = true;
  nullsAtt[Anum_pg_attribute_attacl - 1] = true;
  replacesAtt[Anum_pg_attribute_attacl - 1] = true;
  nullsAtt[Anum_pg_attribute_attoptions - 1] = true;
  replacesAtt[Anum_pg_attribute_attoptions - 1] = true;
  nullsAtt[Anum_pg_attribute_attfdwoptions - 1] = true;
  replacesAtt[Anum_pg_attribute_attfdwoptions - 1] = true;

  tuple = heap_modify_tuple(tuple, RelationGetDescr(attr_rel),
                valuesAtt, nullsAtt, replacesAtt);

  CatalogTupleUpdate(attr_rel, &tuple->t_self, tuple);

  /*
   * Because updating the pg_attribute row will trigger a relcache flush for
   * the target relation, we need not do anything else to notify other
   * backends of the change.
   */

  table_close(attr_rel, RowExclusiveLock);

  RemoveStatistics(relid, attnum);

  relation_close(rel, NoLock);
}

/*
 * heap_drop_with_catalog - removes specified relation from catalogs
 *
 * Note that this routine is not responsible for dropping objects that are
 * linked to the pg_class entry via dependencies (for example, indexes and
 * constraints).  Those are deleted by the dependency-tracing logic in
 * dependency.c before control gets here.  In general, therefore, this routine
 * should never be called directly; go through performDeletion() instead.
 */
void
heap_drop_with_catalog(Oid relid)
{
  Relation  rel;
  HeapTuple tuple;
  Oid     parentOid = InvalidOid,
        defaultPartOid = InvalidOid;

  /*
   * To drop a partition safely, we must grab exclusive lock on its parent,
   * because another backend might be about to execute a query on the parent
   * table.  If it relies on previously cached partition descriptor, then it
   * could attempt to access the just-dropped relation as its partition. We
   * must therefore take a table lock strong enough to prevent all queries
   * on the table from proceeding until we commit and send out a
   * shared-cache-inval notice that will make them update their partition
   * descriptors.
   */
  tuple = SearchSysCache1(RELOID, ObjectIdGetDatum(relid));
  if (!HeapTupleIsValid(tuple))
    elog(ERROR, "cache lookup failed for relation %u", relid);
  if (((Form_pg_class) GETSTRUCT(tuple))->relispartition)
  {
    /*
     * We have to lock the parent if the partition is being detached,
     * because it's possible that some query still has a partition
     * descriptor that includes this partition.
     */
    parentOid = get_partition_parent(relid, true);
    LockRelationOid(parentOid, AccessExclusiveLock);

    /*
     * If this is not the default partition, dropping it will change the
     * default partition's partition constraint, so we must lock it.
     */
    defaultPartOid = get_default_partition_oid(parentOid);
    if (OidIsValid(defaultPartOid) && relid != defaultPartOid)
      LockRelationOid(defaultPartOid, AccessExclusiveLock);
  }

  ReleaseSysCache(tuple);

  /*
   * Open and lock the relation.
   */
  rel = relation_open(relid, AccessExclusiveLock);

  /*
   * There can no longer be anyone *else* touching the relation, but we
   * might still have open queries or cursors, or pending trigger events, in
   * our own session.
   */
  CheckTableNotInUse(rel, "DROP TABLE");

  /*
   * This effectively deletes all rows in the table, and may be done in a
   * serializable transaction.  In that case we must record a rw-conflict in
   * to this transaction from each transaction holding a predicate lock on
   * the table.
   */
  CheckTableForSerializableConflictIn(rel);

  /*
   * Delete pg_foreign_table tuple first.
   */
  if (rel->rd_rel->relkind == RELKIND_FOREIGN_TABLE)
  {
    Relation  ftrel;
    HeapTuple fttuple;

    ftrel = table_open(ForeignTableRelationId, RowExclusiveLock);

    fttuple = SearchSysCache1(FOREIGNTABLEREL, ObjectIdGetDatum(relid));
    if (!HeapTupleIsValid(fttuple))
      elog(ERROR, "cache lookup failed for foreign table %u", relid);

    CatalogTupleDelete(ftrel, &fttuple->t_self);

    ReleaseSysCache(fttuple);
    table_close(ftrel, RowExclusiveLock);
  }

  /*
   * If a partitioned table, delete the pg_partitioned_table tuple.
   */
  if (rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
    RemovePartitionKeyByRelId(relid);

  /*
   * If the relation being dropped is the default partition itself,
   * invalidate its entry in pg_partitioned_table.
   */
  if (relid == defaultPartOid)
    update_default_partition_oid(parentOid, InvalidOid);

  /*
   * Schedule unlinking of the relation's physical files at commit.
   */
  if (RELKIND_HAS_STORAGE(rel->rd_rel->relkind))
    RelationDropStorage(rel);

  /* ensure that stats are dropped if transaction commits */
  pgstat_drop_relation(rel);

  /*
   * Close relcache entry, but *keep* AccessExclusiveLock on the relation
   * until transaction commit.  This ensures no one else will try to do
   * something with the doomed relation.
   */
  relation_close(rel, NoLock);

  /*
   * Remove any associated relation synchronization states.
   */
  RemoveSubscriptionRel(InvalidOid, relid);

  /*
   * Forget any ON COMMIT action for the rel
   */
  remove_on_commit_action(relid);

  /*
   * Flush the relation from the relcache.  We want to do this before
   * starting to remove catalog entries, just to be certain that no relcache
   * entry rebuild will happen partway through.  (That should not really
   * matter, since we don't do CommandCounterIncrement here, but let's be
   * safe.)
   */
  RelationForgetRelation(relid);

  /*
   * remove inheritance information
   */
  RelationRemoveInheritance(relid);

  /*
   * delete statistics
   */
  RemoveStatistics(relid, 0);

  /*
   * delete attribute tuples
   */
  DeleteAttributeTuples(relid);

  /*
   * delete relation tuple
   */
  DeleteRelationTuple(relid);

  if (OidIsValid(parentOid))
  {
    /*
     * If this is not the default partition, the partition constraint of
     * the default partition has changed to include the portion of the key
     * space previously covered by the dropped partition.
     */
    if (OidIsValid(defaultPartOid) && relid != defaultPartOid)
      CacheInvalidateRelcacheByRelid(defaultPartOid);

    /*
     * Invalidate the parent's relcache so that the partition is no longer
     * included in its partition descriptor.
     */
    CacheInvalidateRelcacheByRelid(parentOid);
    /* keep the lock */
  }
}


/*
 * RelationClearMissing
 *
 * Set atthasmissing and attmissingval to false/null for all attributes
 * where they are currently set. This can be safely and usefully done if
 * the table is rewritten (e.g. by VACUUM FULL or CLUSTER) where we know there
 * are no rows left with less than a full complement of attributes.
 *
 * The caller must have an AccessExclusive lock on the relation.
 */
void
RelationClearMissing(Relation rel)
{
  Relation  attr_rel;
  Oid     relid = RelationGetRelid(rel);
  int     natts = RelationGetNumberOfAttributes(rel);
  int     attnum;
  Datum   repl_val[Natts_pg_attribute];
  bool    repl_null[Natts_pg_attribute];
  bool    repl_repl[Natts_pg_attribute];
  Form_pg_attribute attrtuple;
  HeapTuple tuple,
        newtuple;

  memset(repl_val, 0, sizeof(repl_val));
  memset(repl_null, false, sizeof(repl_null));
  memset(repl_repl, false, sizeof(repl_repl));

  repl_val[Anum_pg_attribute_atthasmissing - 1] = BoolGetDatum(false);
  repl_null[Anum_pg_attribute_attmissingval - 1] = true;

  repl_repl[Anum_pg_attribute_atthasmissing - 1] = true;
  repl_repl[Anum_pg_attribute_attmissingval - 1] = true;


  /* Get a lock on pg_attribute */
  attr_rel = table_open(AttributeRelationId, RowExclusiveLock);

  /* process each non-system attribute, including any dropped columns */
  for (attnum = 1; attnum <= natts; attnum++)
  {
    tuple = SearchSysCache2(ATTNUM,
                ObjectIdGetDatum(relid),
                Int16GetDatum(attnum));
    if (!HeapTupleIsValid(tuple))  /* shouldn't happen */
      elog(ERROR, "cache lookup failed for attribute %d of relation %u",
         attnum, relid);

    attrtuple = (Form_pg_attribute) GETSTRUCT(tuple);

    /* ignore any where atthasmissing is not true */
    if (attrtuple->atthasmissing)
    {
      newtuple = heap_modify_tuple(tuple, RelationGetDescr(attr_rel),
                     repl_val, repl_null, repl_repl);

      CatalogTupleUpdate(attr_rel, &newtuple->t_self, newtuple);

      heap_freetuple(newtuple);
    }

    ReleaseSysCache(tuple);
  }

  /*
   * Our update of the pg_attribute rows will force a relcache rebuild, so
   * there's nothing else to do here.
   */
  table_close(attr_rel, RowExclusiveLock);
}

/*
 * StoreAttrMissingVal
 *
 * Set the missing value of a single attribute.
 */
void
StoreAttrMissingVal(Relation rel, AttrNumber attnum, Datum missingval)
{
  Datum   valuesAtt[Natts_pg_attribute] = {0};
  bool    nullsAtt[Natts_pg_attribute] = {0};
  bool    replacesAtt[Natts_pg_attribute] = {0};
  Relation  attrrel;
  Form_pg_attribute attStruct;
  HeapTuple atttup,
        newtup;

  /* This is only supported for plain tables */
  Assert(rel->rd_rel->relkind == RELKIND_RELATION);

  /* Fetch the pg_attribute row */
  attrrel = table_open(AttributeRelationId, RowExclusiveLock);

  atttup = SearchSysCache2(ATTNUM,
               ObjectIdGetDatum(RelationGetRelid(rel)),
               Int16GetDatum(attnum));
  if (!HeapTupleIsValid(atttup)) /* shouldn't happen */
    elog(ERROR, "cache lookup failed for attribute %d of relation %u",
       attnum, RelationGetRelid(rel));
  attStruct = (Form_pg_attribute) GETSTRUCT(atttup);

  /* Make a one-element array containing the value */
  missingval = PointerGetDatum(construct_array(&missingval,
                         1,
                         attStruct->atttypid,
                         attStruct->attlen,
                         attStruct->attbyval,
                         attStruct->attalign));

  /* Update the pg_attribute row */
  valuesAtt[Anum_pg_attribute_atthasmissing - 1] = BoolGetDatum(true);
  replacesAtt[Anum_pg_attribute_atthasmissing - 1] = true;

  valuesAtt[Anum_pg_attribute_attmissingval - 1] = missingval;
  replacesAtt[Anum_pg_attribute_attmissingval - 1] = true;

  newtup = heap_modify_tuple(atttup, RelationGetDescr(attrrel),
                 valuesAtt, nullsAtt, replacesAtt);
  CatalogTupleUpdate(attrrel, &newtup->t_self, newtup);

  /* clean up */
  ReleaseSysCache(atttup);
  table_close(attrrel, RowExclusiveLock);
}

/*
 * SetAttrMissing
 *
 * Set the missing value of a single attribute. This should only be used by
 * binary upgrade. Takes an AccessExclusive lock on the relation owning the
 * attribute.
 */
void
SetAttrMissing(Oid relid, char *attname, char *value)
{
  Datum   valuesAtt[Natts_pg_attribute] = {0};
  bool    nullsAtt[Natts_pg_attribute] = {0};
  bool    replacesAtt[Natts_pg_attribute] = {0};
  Datum   missingval;
  Form_pg_attribute attStruct;
  Relation  attrrel,
        tablerel;
  HeapTuple atttup,
        newtup;

  /* lock the table the attribute belongs to */
  tablerel = table_open(relid, AccessExclusiveLock);

  /* Don't do anything unless it's a plain table */
  if (tablerel->rd_rel->relkind != RELKIND_RELATION)
  {
    table_close(tablerel, AccessExclusiveLock);
    return;
  }

  /* Lock the attribute row and get the data */
  attrrel = table_open(AttributeRelationId, RowExclusiveLock);
  atttup = SearchSysCacheAttName(relid, attname);
  if (!HeapTupleIsValid(atttup))
    elog(ERROR, "cache lookup failed for attribute %s of relation %u",
       attname, relid);
  attStruct = (Form_pg_attribute) GETSTRUCT(atttup);

  /* get an array value from the value string */
  missingval = OidFunctionCall3(F_ARRAY_IN,
                  CStringGetDatum(value),
                  ObjectIdGetDatum(attStruct->atttypid),
                  Int32GetDatum(attStruct->atttypmod));

  /* update the tuple - set atthasmissing and attmissingval */
  valuesAtt[Anum_pg_attribute_atthasmissing - 1] = BoolGetDatum(true);
  replacesAtt[Anum_pg_attribute_atthasmissing - 1] = true;
  valuesAtt[Anum_pg_attribute_attmissingval - 1] = missingval;
  replacesAtt[Anum_pg_attribute_attmissingval - 1] = true;

  newtup = heap_modify_tuple(atttup, RelationGetDescr(attrrel),
                 valuesAtt, nullsAtt, replacesAtt);
  CatalogTupleUpdate(attrrel, &newtup->t_self, newtup);

  /* clean up */
  ReleaseSysCache(atttup);
  table_close(attrrel, RowExclusiveLock);
  table_close(tablerel, AccessExclusiveLock);
}

/*
 * Store a check-constraint expression for the given relation.
 *
 * Caller is responsible for updating the count of constraints
 * in the pg_class entry for the relation.
 *
 * The OID of the new constraint is returned.
 */
static Oid
StoreRelCheck(Relation rel, const char *ccname, Node *expr,
        bool is_enforced, bool is_validated, bool is_local,
        int16 inhcount, bool is_no_inherit, bool is_internal)
{
  char     *ccbin;
  List     *varList;
  int     keycount;
  int16    *attNos;
  Oid     constrOid;

  /*
   * Flatten expression to string form for storage.
   */
  ccbin = nodeToString(expr);

  /*
   * Find columns of rel that are used in expr
   *
   * NB: pull_var_clause is okay here only because we don't allow subselects
   * in check constraints; it would fail to examine the contents of
   * subselects.
   */
  varList = pull_var_clause(expr, 0);
  keycount = list_length(varList);

  if (keycount > 0)
  {
    ListCell   *vl;
    int     i = 0;

    attNos = (int16 *) palloc(keycount * sizeof(int16));
    foreach(vl, varList)
    {
      Var      *var = (Var *) lfirst(vl);
      int     j;

      for (j = 0; j < i; j++)
        if (attNos[j] == var->varattno)
          break;
      if (j == i)
        attNos[i++] = var->varattno;
    }
    keycount = i;
  }
  else
    attNos = NULL;

  /*
   * Partitioned tables do not contain any rows themselves, so a NO INHERIT
   * constraint makes no sense.
   */
  if (is_no_inherit &&
    rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
    ereport(ERROR,
        (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
         errmsg("cannot add NO INHERIT constraint to partitioned table \"%s\"",
            RelationGetRelationName(rel))));

  /*
   * Create the Check Constraint
   */
  constrOid =
    CreateConstraintEntry(ccname, /* Constraint Name */
                RelationGetNamespace(rel),  /* namespace */
                CONSTRAINT_CHECK, /* Constraint Type */
                false,  /* Is Deferrable */
                false,  /* Is Deferred */
                is_enforced,  /* Is Enforced */
                is_validated,
                InvalidOid, /* no parent constraint */
                RelationGetRelid(rel),  /* relation */
                attNos, /* attrs in the constraint */
                keycount, /* # key attrs in the constraint */
                keycount, /* # total attrs in the constraint */
                InvalidOid, /* not a domain constraint */
                InvalidOid, /* no associated index */
                InvalidOid, /* Foreign key fields */
                NULL,
                NULL,
                NULL,
                NULL,
                0,
                ' ',
                ' ',
                NULL,
                0,
                ' ',
                NULL, /* not an exclusion constraint */
                expr, /* Tree form of check constraint */
                ccbin,  /* Binary form of check constraint */
                is_local, /* conislocal */
                inhcount, /* coninhcount */
                is_no_inherit,  /* connoinherit */
                false,  /* conperiod */
                is_internal); /* internally constructed? */

  pfree(ccbin);

  return constrOid;
}

/*
 * Store a not-null constraint for the given relation
 *
 * The OID of the new constraint is returned.
 */
static Oid
StoreRelNotNull(Relation rel, const char *nnname, AttrNumber attnum,
        bool is_validated, bool is_local, int inhcount,
        bool is_no_inherit)
{
  Oid     constrOid;

  Assert(attnum > InvalidAttrNumber);

  constrOid =
    CreateConstraintEntry(nnname,
                RelationGetNamespace(rel),
                CONSTRAINT_NOTNULL,
                false,
                false,
                true, /* Is Enforced */
                is_validated,
                InvalidOid,
                RelationGetRelid(rel),
                &attnum,
                1,
                1,
                InvalidOid, /* not a domain constraint */
                InvalidOid, /* no associated index */
                InvalidOid, /* Foreign key fields */
                NULL,
                NULL,
                NULL,
                NULL,
                0,
                ' ',
                ' ',
                NULL,
                0,
                ' ',
                NULL, /* not an exclusion constraint */
                NULL,
                NULL,
                is_local,
                inhcount,
                is_no_inherit,
                false,
                false);
  return constrOid;
}

/*
 * Store defaults and CHECK constraints (passed as a list of CookedConstraint).
 *
 * Each CookedConstraint struct is modified to store the new catalog tuple OID.
 *
 * NOTE: only pre-cooked expressions will be passed this way, which is to
 * say expressions inherited from an existing relation.  Newly parsed
 * expressions can be added later, by direct calls to StoreAttrDefault
 * and StoreRelCheck (see AddRelationNewConstraints()).
 */
static void
StoreConstraints(Relation rel, List *cooked_constraints, bool is_internal)
{
  int     numchecks = 0;
  ListCell   *lc;

  if (cooked_constraints == NIL)
    return;         /* nothing to do */

  /*
   * Deparsing of constraint expressions will fail unless the just-created
   * pg_attribute tuples for this relation are made visible.  So, bump the
   * command counter.  CAUTION: this will cause a relcache entry rebuild.
   */
  CommandCounterIncrement();

  foreach(lc, cooked_constraints)
  {
    CookedConstraint *con = (CookedConstraint *) lfirst(lc);

    switch (con->contype)
    {
      case CONSTR_DEFAULT:
        con->conoid = StoreAttrDefault(rel, con->attnum, con->expr,
                         is_internal);
        break;
      case CONSTR_CHECK:
        con->conoid =
          StoreRelCheck(rel, con->name, con->expr,
                  con->is_enforced, !con->skip_validation,
                  con->is_local, con->inhcount,
                  con->is_no_inherit, is_internal);
        numchecks++;
        break;

      default:
        elog(ERROR, "unrecognized constraint type: %d",
           (int) con->contype);
    }
  }

  if (numchecks > 0)
    SetRelationNumChecks(rel, numchecks);
}

/*
 * AddRelationNewConstraints
 *
 * Add new column default expressions and/or constraint check expressions
 * to an existing relation.  This is defined to do both for efficiency in
 * DefineRelation, but of course you can do just one or the other by passing
 * empty lists.
 *
 * rel: relation to be modified
 * newColDefaults: list of RawColumnDefault structures
 * newConstraints: list of Constraint nodes
 * allow_merge: true if check constraints may be merged with existing ones
 * is_local: true if definition is local, false if it's inherited
 * is_internal: true if result of some internal process, not a user request
 * queryString: used during expression transformation of default values and
 *    cooked CHECK constraints
 *
 * All entries in newColDefaults will be processed.  Entries in newConstraints
 * will be processed only if they are CONSTR_CHECK or CONSTR_NOTNULL types.
 *
 * Returns a list of CookedConstraint nodes that shows the cooked form of
 * the default and constraint expressions added to the relation.
 *
 * NB: caller should have opened rel with some self-conflicting lock mode,
 * and should hold that lock till end of transaction; for normal cases that'll
 * be AccessExclusiveLock, but if caller knows that the constraint is already
 * enforced by some other means, it can be ShareUpdateExclusiveLock.  Also, we
 * assume the caller has done a CommandCounterIncrement if necessary to make
 * the relation's catalog tuples visible.
 */
List *
AddRelationNewConstraints(Relation rel,
              List *newColDefaults,
              List *newConstraints,
              bool allow_merge,
              bool is_local,
              bool is_internal,
              const char *queryString)
{
  List     *cookedConstraints = NIL;
  TupleDesc tupleDesc;
  TupleConstr *oldconstr;
  int     numoldchecks;
  ParseState *pstate;
  ParseNamespaceItem *nsitem;
  int     numchecks;
  List     *checknames;
  List     *nnnames;
  Node     *expr;
  CookedConstraint *cooked;

  /*
   * Get info about existing constraints.
   */
  tupleDesc = RelationGetDescr(rel);
  oldconstr = tupleDesc->constr;
  if (oldconstr)
    numoldchecks = oldconstr->num_check;
  else
    numoldchecks = 0;

  /*
   * Create a dummy ParseState and insert the target relation as its sole
   * rangetable entry.  We need a ParseState for transformExpr.
   */
  pstate = make_parsestate(NULL);
  pstate->p_sourcetext = queryString;
  nsitem = addRangeTableEntryForRelation(pstate,
                       rel,
                       AccessShareLock,
                       NULL,
                       false,
                       true);
  addNSItemToQuery(pstate, nsitem, true, true, true);

  /*
   * Process column default expressions.
   */
  foreach_ptr(RawColumnDefault, colDef, newColDefaults)
  {
    Form_pg_attribute atp = TupleDescAttr(rel->rd_att, colDef->attnum - 1);
    Oid     defOid;

    expr = cookDefault(pstate, colDef->raw_default,
               atp->atttypid, atp->atttypmod,
               NameStr(atp->attname),
               atp->attgenerated);

    /*
     * If the expression is just a NULL constant, we do not bother to make
     * an explicit pg_attrdef entry, since the default behavior is
     * equivalent.  This applies to column defaults, but not for
     * generation expressions.
     *
     * Note a nonobvious property of this test: if the column is of a
     * domain type, what we'll get is not a bare null Const but a
     * CoerceToDomain expr, so we will not discard the default.  This is
     * critical because the column default needs to be retained to
     * override any default that the domain might have.
     */
    if (expr == NULL ||
      (!colDef->generated &&
       IsA(expr, Const) &&
       castNode(Const, expr)->constisnull))
      continue;

    defOid = StoreAttrDefault(rel, colDef->attnum, expr, is_internal);

    cooked = (CookedConstraint *) palloc(sizeof(CookedConstraint));
    cooked->contype = CONSTR_DEFAULT;
    cooked->conoid = defOid;
    cooked->name = NULL;
    cooked->attnum = colDef->attnum;
    cooked->expr = expr;
    cooked->is_enforced = true;
    cooked->skip_validation = false;
    cooked->is_local = is_local;
    cooked->inhcount = is_local ? 0 : 1;
    cooked->is_no_inherit = false;
    cookedConstraints = lappend(cookedConstraints, cooked);
  }

  /*
   * Process constraint expressions.
   */
  numchecks = numoldchecks;
  checknames = NIL;
  nnnames = NIL;
  foreach_node(Constraint, cdef, newConstraints)
  {
    Oid     constrOid;

    if (cdef->contype == CONSTR_CHECK)
    {
      char     *ccname;

      if (cdef->raw_expr != NULL)
      {
        Assert(cdef->cooked_expr == NULL);

        /*
         * Transform raw parsetree to executable expression, and
         * verify it's valid as a CHECK constraint.
         */
        expr = cookConstraint(pstate, cdef->raw_expr,
                    RelationGetRelationName(rel));
      }
      else
      {
        Assert(cdef->cooked_expr != NULL);

        /*
         * Here, we assume the parser will only pass us valid CHECK
         * expressions, so we do no particular checking.
         */
        expr = stringToNode(cdef->cooked_expr);
      }

      /*
       * Check name uniqueness, or generate a name if none was given.
       */
      if (cdef->conname != NULL)
      {
        ccname = cdef->conname;
        /* Check against other new constraints */
        /* Needed because we don't do CommandCounterIncrement in loop */
        foreach_ptr(char, chkname, checknames)
        {
          if (strcmp(chkname, ccname) == 0)
            ereport(ERROR,
                (errcode(ERRCODE_DUPLICATE_OBJECT),
                 errmsg("check constraint \"%s\" already exists",
                    ccname)));
        }

        /* save name for future checks */
        checknames = lappend(checknames, ccname);

        /*
         * Check against pre-existing constraints.  If we are allowed
         * to merge with an existing constraint, there's no more to do
         * here. (We omit the duplicate constraint from the result,
         * which is what ATAddCheckNNConstraint wants.)
         */
        if (MergeWithExistingConstraint(rel, ccname, expr,
                        allow_merge, is_local,
                        cdef->is_enforced,
                        cdef->initially_valid,
                        cdef->is_no_inherit))
          continue;
      }
      else
      {
        /*
         * When generating a name, we want to create "tab_col_check"
         * for a column constraint and "tab_check" for a table
         * constraint.  We no longer have any info about the syntactic
         * positioning of the constraint phrase, so we approximate
         * this by seeing whether the expression references more than
         * one column.  (If the user played by the rules, the result
         * is the same...)
         *
         * Note: pull_var_clause() doesn't descend into sublinks, but
         * we eliminated those above; and anyway this only needs to be
         * an approximate answer.
         */
        List     *vars;
        char     *colname;

        vars = pull_var_clause(expr, 0);

        /* eliminate duplicates */
        vars = list_union(NIL, vars);

        if (list_length(vars) == 1)
          colname = get_attname(RelationGetRelid(rel),
                      ((Var *) linitial(vars))->varattno,
                      true);
        else
          colname = NULL;

        ccname = ChooseConstraintName(RelationGetRelationName(rel),
                        colname,
                        "check",
                        RelationGetNamespace(rel),
                        checknames);

        /* save name for future checks */
        checknames = lappend(checknames, ccname);
      }

      /*
       * OK, store it.
       */
      constrOid =
        StoreRelCheck(rel, ccname, expr, cdef->is_enforced,
                cdef->initially_valid, is_local,
                is_local ? 0 : 1, cdef->is_no_inherit,
                is_internal);

      numchecks++;

      cooked = (CookedConstraint *) palloc(sizeof(CookedConstraint));
      cooked->contype = CONSTR_CHECK;
      cooked->conoid = constrOid;
      cooked->name = ccname;
      cooked->attnum = 0;
      cooked->expr = expr;
      cooked->is_enforced = cdef->is_enforced;
      cooked->skip_validation = cdef->skip_validation;
      cooked->is_local = is_local;
      cooked->inhcount = is_local ? 0 : 1;
      cooked->is_no_inherit = cdef->is_no_inherit;
      cookedConstraints = lappend(cookedConstraints, cooked);
    }
    else if (cdef->contype == CONSTR_NOTNULL)
    {
      CookedConstraint *nncooked;
      AttrNumber  colnum;
      int16   inhcount = is_local ? 0 : 1;
      char     *nnname;

      /* Determine which column to modify */
      colnum = get_attnum(RelationGetRelid(rel), strVal(linitial(cdef->keys)));
      if (colnum == InvalidAttrNumber)
        ereport(ERROR,
            errcode(ERRCODE_UNDEFINED_COLUMN),
            errmsg("column \"%s\" of relation \"%s\" does not exist",
                 strVal(linitial(cdef->keys)), RelationGetRelationName(rel)));
      if (colnum < InvalidAttrNumber)
        ereport(ERROR,
            errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
            errmsg("cannot add not-null constraint on system column \"%s\"",
                 strVal(linitial(cdef->keys))));

      Assert(cdef->initially_valid != cdef->skip_validation);

      /*
       * If the column already has a not-null constraint, we don't want
       * to add another one; adjust inheritance status as needed.  This
       * also checks whether the existing constraint matches the
       * requested validity.
       */
      if (AdjustNotNullInheritance(RelationGetRelid(rel), colnum,
                     is_local, cdef->is_no_inherit,
                     cdef->skip_validation))
        continue;

      /*
       * If a constraint name is specified, check that it isn't already
       * used.  Otherwise, choose a non-conflicting one ourselves.
       */
      if (cdef->conname)
      {
        if (ConstraintNameIsUsed(CONSTRAINT_RELATION,
                     RelationGetRelid(rel),
                     cdef->conname))
          ereport(ERROR,
              errcode(ERRCODE_DUPLICATE_OBJECT),
              errmsg("constraint \"%s\" for relation \"%s\" already exists",
                   cdef->conname, RelationGetRelationName(rel)));
        nnname = cdef->conname;
      }
      else
        nnname = ChooseConstraintName(RelationGetRelationName(rel),
                        strVal(linitial(cdef->keys)),
                        "not_null",
                        RelationGetNamespace(rel),
                        nnnames);
      nnnames = lappend(nnnames, nnname);

      constrOid =
        StoreRelNotNull(rel, nnname, colnum,
                cdef->initially_valid,
                is_local,
                inhcount,
                cdef->is_no_inherit);

      nncooked = (CookedConstraint *) palloc(sizeof(CookedConstraint));
      nncooked->contype = CONSTR_NOTNULL;
      nncooked->conoid = constrOid;
      nncooked->name = nnname;
      nncooked->attnum = colnum;
      nncooked->expr = NULL;
      nncooked->is_enforced = true;
      nncooked->skip_validation = cdef->skip_validation;
      nncooked->is_local = is_local;
      nncooked->inhcount = inhcount;
      nncooked->is_no_inherit = cdef->is_no_inherit;

      cookedConstraints = lappend(cookedConstraints, nncooked);
    }
  }

  /*
   * Update the count of constraints in the relation's pg_class tuple. We do
   * this even if there was no change, in order to ensure that an SI update
   * message is sent out for the pg_class tuple, which will force other
   * backends to rebuild their relcache entries for the rel. (This is
   * critical if we added defaults but not constraints.)
   */
  SetRelationNumChecks(rel, numchecks);

  return cookedConstraints;
}

/*
 * Check for a pre-existing check constraint that conflicts with a proposed
 * new one, and either adjust its conislocal/coninhcount settings or throw
 * error as needed.
 *
 * Returns true if merged (constraint is a duplicate), or false if it's
 * got a so-far-unique name, or throws error if conflict.
 *
 * XXX See MergeConstraintsIntoExisting too if you change this code.
 */
static bool
MergeWithExistingConstraint(Relation rel, const char *ccname, Node *expr,
              bool allow_merge, bool is_local,
              bool is_enforced,
              bool is_initially_valid,
              bool is_no_inherit)
{
  bool    found;
  Relation  conDesc;
  SysScanDesc conscan;
  ScanKeyData skey[3];
  HeapTuple tup;

  /* Search for a pg_constraint entry with same name and relation */
  conDesc = table_open(ConstraintRelationId, RowExclusiveLock);

  found = false;

  ScanKeyInit(&skey[0],
        Anum_pg_constraint_conrelid,
        BTEqualStrategyNumber, F_OIDEQ,
        ObjectIdGetDatum(RelationGetRelid(rel)));
  ScanKeyInit(&skey[1],
        Anum_pg_constraint_contypid,
        BTEqualStrategyNumber, F_OIDEQ,
        ObjectIdGetDatum(InvalidOid));
  ScanKeyInit(&skey[2],
        Anum_pg_constraint_conname,
        BTEqualStrategyNumber, F_NAMEEQ,
        CStringGetDatum(ccname));

  conscan = systable_beginscan(conDesc, ConstraintRelidTypidNameIndexId, true,
                 NULL, 3, skey);

  /* There can be at most one matching row */
  if (HeapTupleIsValid(tup = systable_getnext(conscan)))
  {
    Form_pg_constraint con = (Form_pg_constraint) GETSTRUCT(tup);

    /* Found it.  Conflicts if not identical check constraint */
    if (con->contype == CONSTRAINT_CHECK)
    {
      Datum   val;
      bool    isnull;

      val = fastgetattr(tup,
                Anum_pg_constraint_conbin,
                conDesc->rd_att, &isnull);
      if (isnull)
        elog(ERROR, "null conbin for rel %s",
           RelationGetRelationName(rel));
      if (equal(expr, stringToNode(TextDatumGetCString(val))))
        found = true;
    }

    /*
     * If the existing constraint is purely inherited (no local
     * definition) then interpret addition of a local constraint as a
     * legal merge.  This allows ALTER ADD CONSTRAINT on parent and child
     * tables to be given in either order with same end state.  However if
     * the relation is a partition, all inherited constraints are always
     * non-local, including those that were merged.
     */
    if (is_local && !con->conislocal && !rel->rd_rel->relispartition)
      allow_merge = true;

    if (!found || !allow_merge)
      ereport(ERROR,
          (errcode(ERRCODE_DUPLICATE_OBJECT),
           errmsg("constraint \"%s\" for relation \"%s\" already exists",
              ccname, RelationGetRelationName(rel))));

    /* If the child constraint is "no inherit" then cannot merge */
    if (con->connoinherit)
      ereport(ERROR,
          (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
           errmsg("constraint \"%s\" conflicts with non-inherited constraint on relation \"%s\"",
              ccname, RelationGetRelationName(rel))));

    /*
     * Must not change an existing inherited constraint to "no inherit"
     * status.  That's because inherited constraints should be able to
     * propagate to lower-level children.
     */
    if (con->coninhcount > 0 && is_no_inherit)
      ereport(ERROR,
          (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
           errmsg("constraint \"%s\" conflicts with inherited constraint on relation \"%s\"",
              ccname, RelationGetRelationName(rel))));

    /*
     * If the child constraint is "not valid" then cannot merge with a
     * valid parent constraint.
     */
    if (is_initially_valid && con->conenforced && !con->convalidated)
      ereport(ERROR,
          (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
           errmsg("constraint \"%s\" conflicts with NOT VALID constraint on relation \"%s\"",
              ccname, RelationGetRelationName(rel))));

    /*
     * A non-enforced child constraint cannot be merged with an enforced
     * parent constraint. However, the reverse is allowed, where the child
     * constraint is enforced.
     */
    if ((!is_local && is_enforced && !con->conenforced) ||
      (is_local && !is_enforced && con->conenforced))
      ereport(ERROR,
          (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
           errmsg("constraint \"%s\" conflicts with NOT ENFORCED constraint on relation \"%s\"",
              ccname, RelationGetRelationName(rel))));

    /* OK to update the tuple */
    ereport(NOTICE,
        (errmsg("merging constraint \"%s\" with inherited definition",
            ccname)));

    tup = heap_copytuple(tup);
    con = (Form_pg_constraint) GETSTRUCT(tup);

    /*
     * In case of partitions, an inherited constraint must be inherited
     * only once since it cannot have multiple parents and it is never
     * considered local.
     */
    if (rel->rd_rel->relispartition)
    {
      con->coninhcount = 1;
      con->conislocal = false;
    }
    else
    {
      if (is_local)
        con->conislocal = true;
      else if (pg_add_s16_overflow(con->coninhcount, 1,
                     &con->coninhcount))
        ereport(ERROR,
            errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
            errmsg("too many inheritance parents"));
    }

    if (is_no_inherit)
    {
      Assert(is_local);
      con->connoinherit = true;
    }

    /*
     * If the child constraint is required to be enforced while the parent
     * constraint is not, this should be allowed by marking the child
     * constraint as enforced. In the reverse case, an error would have
     * already been thrown before reaching this point.
     */
    if (is_enforced && !con->conenforced)
    {
      Assert(is_local);
      con->conenforced = true;
      con->convalidated = true;
    }

    CatalogTupleUpdate(conDesc, &tup->t_self, tup);
  }

  systable_endscan(conscan);
  table_close(conDesc, RowExclusiveLock);

  return found;
}

/*
 * Create the not-null constraints when creating a new relation
 *
 * These come from two sources: the 'constraints' list (of Constraint) is
 * specified directly by the user; the 'old_notnulls' list (of
 * CookedConstraint) comes from inheritance.  We create one constraint
 * for each column, giving priority to user-specified ones, and setting
 * inhcount according to how many parents cause each column to get a
 * not-null constraint.  If a user-specified name clashes with another
 * user-specified name, an error is raised.
 *
 * Returns a list of AttrNumber for columns that need to have the attnotnull
 * flag set.
 */
List *
AddRelationNotNullConstraints(Relation rel, List *constraints,
                List *old_notnulls)
{
  List     *givennames;
  List     *nnnames;
  List     *nncols = NIL;

  /*
   * We track two lists of names: nnnames keeps all the constraint names,
   * givennames tracks user-generated names.  The distinction is important,
   * because we must raise error for user-generated name conflicts, but for
   * system-generated name conflicts we just generate another.
   */
  nnnames = NIL;
  givennames = NIL;

  /*
   * First, create all not-null constraints that are directly specified by
   * the user.  Note that inheritance might have given us another source for
   * each, so we must scan the old_notnulls list and increment inhcount for
   * each element with identical attnum.  We delete from there any element
   * that we process.
   *
   * We don't use foreach() here because we have two nested loops over the
   * constraint list, with possible element deletions in the inner one. If
   * we used foreach_delete_current() it could only fix up the state of one
   * of the loops, so it seems cleaner to use looping over list indexes for
   * both loops.  Note that any deletion will happen beyond where the outer
   * loop is, so its index never needs adjustment.
   */
  for (int outerpos = 0; outerpos < list_length(constraints); outerpos++)
  {
    Constraint *constr;
    AttrNumber  attnum;
    char     *conname;
    int     inhcount = 0;

    constr = list_nth_node(Constraint, constraints, outerpos);

    Assert(constr->contype == CONSTR_NOTNULL);

    attnum = get_attnum(RelationGetRelid(rel),
              strVal(linitial(constr->keys)));
    if (attnum == InvalidAttrNumber)
      ereport(ERROR,
          errcode(ERRCODE_UNDEFINED_COLUMN),
          errmsg("column \"%s\" of relation \"%s\" does not exist",
               strVal(linitial(constr->keys)),
               RelationGetRelationName(rel)));
    if (attnum < InvalidAttrNumber)
      ereport(ERROR,
          errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
          errmsg("cannot add not-null constraint on system column \"%s\"",
               strVal(linitial(constr->keys))));

    /*
     * A column can only have one not-null constraint, so discard any
     * additional ones that appear for columns we already saw; but check
     * that the NO INHERIT flags match.
     */
    for (int restpos = outerpos + 1; restpos < list_length(constraints);)
    {
      Constraint *other;

      other = list_nth_node(Constraint, constraints, restpos);
      if (strcmp(strVal(linitial(constr->keys)),
             strVal(linitial(other->keys))) == 0)
      {
        if (other->is_no_inherit != constr->is_no_inherit)
          ereport(ERROR,
              errcode(ERRCODE_SYNTAX_ERROR),
              errmsg("conflicting NO INHERIT declaration for not-null constraint on column \"%s\"",
                   strVal(linitial(constr->keys))));

        /*
         * Preserve constraint name if one is specified, but raise an
         * error if conflicting ones are specified.
         */
        if (other->conname)
        {
          if (!constr->conname)
            constr->conname = pstrdup(other->conname);
          else if (strcmp(constr->conname, other->conname) != 0)
            ereport(ERROR,
                errcode(ERRCODE_SYNTAX_ERROR),
                errmsg("conflicting not-null constraint names \"%s\" and \"%s\"",
                     constr->conname, other->conname));
        }

        /* XXX do we need to verify any other fields? */
        constraints = list_delete_nth_cell(constraints, restpos);
      }
      else
        restpos++;
    }

    /*
     * Search in the list of inherited constraints for any entries on the
     * same column; determine an inheritance count from that.  Also, if at
     * least one parent has a constraint for this column, then we must not
     * accept a user specification for a NO INHERIT one.  Any constraint
     * from parents that we process here is deleted from the list: we no
     * longer need to process it in the loop below.
     */
    foreach_ptr(CookedConstraint, old, old_notnulls)
    {
      if (old->attnum == attnum)
      {
        /*
         * If we get a constraint from the parent, having a local NO
         * INHERIT one doesn't work.
         */
        if (constr->is_no_inherit)
          ereport(ERROR,
              (errcode(ERRCODE_DATATYPE_MISMATCH),
               errmsg("cannot define not-null constraint with NO INHERIT on column \"%s\"",
                  strVal(linitial(constr->keys))),
               errdetail("The column has an inherited not-null constraint.")));

        inhcount++;
        old_notnulls = foreach_delete_current(old_notnulls, old);
      }
    }

    /*
     * Determine a constraint name, which may have been specified by the
     * user, or raise an error if a conflict exists with another
     * user-specified name.
     */
    if (constr->conname)
    {
      foreach_ptr(char, thisname, givennames)
      {
        if (strcmp(thisname, constr->conname) == 0)
          ereport(ERROR,
              errcode(ERRCODE_DUPLICATE_OBJECT),
              errmsg("constraint \"%s\" for relation \"%s\" already exists",
                   constr->conname,
                   RelationGetRelationName(rel)));
      }

      conname = constr->conname;
      givennames = lappend(givennames, conname);
    }
    else
      conname = ChooseConstraintName(RelationGetRelationName(rel),
                       get_attname(RelationGetRelid(rel),
                             attnum, false),
                       "not_null",
                       RelationGetNamespace(rel),
                       nnnames);
    nnnames = lappend(nnnames, conname);

    StoreRelNotNull(rel, conname,
            attnum, true, true,
            inhcount, constr->is_no_inherit);

    nncols = lappend_int(nncols, attnum);
  }

  /*
   * If any column remains in the old_notnulls list, we must create a not-
   * null constraint marked not-local for that column.  Because multiple
   * parents could specify a not-null constraint for the same column, we
   * must count how many there are and set an appropriate inhcount
   * accordingly, deleting elements we've already processed.
   *
   * We don't use foreach() here because we have two nested loops over the
   * constraint list, with possible element deletions in the inner one. If
   * we used foreach_delete_current() it could only fix up the state of one
   * of the loops, so it seems cleaner to use looping over list indexes for
   * both loops.  Note that any deletion will happen beyond where the outer
   * loop is, so its index never needs adjustment.
   */
  for (int outerpos = 0; outerpos < list_length(old_notnulls); outerpos++)
  {
    CookedConstraint *cooked;
    char     *conname = NULL;
    int     inhcount = 1;

    cooked = (CookedConstraint *) list_nth(old_notnulls, outerpos);
    Assert(cooked->contype == CONSTR_NOTNULL);
    Assert(cooked->name);

    /*
     * Preserve the first non-conflicting constraint name we come across.
     */
    if (conname == NULL)
      conname = cooked->name;

    for (int restpos = outerpos + 1; restpos < list_length(old_notnulls);)
    {
      CookedConstraint *other;

      other = (CookedConstraint *) list_nth(old_notnulls, restpos);
      Assert(other->name);
      if (other->attnum == cooked->attnum)
      {
        if (conname == NULL)
          conname = other->name;

        inhcount++;
        old_notnulls = list_delete_nth_cell(old_notnulls, restpos);
      }
      else
        restpos++;
    }

    /* If we got a name, make sure it isn't one we've already used */
    if (conname != NULL)
    {
      foreach_ptr(char, thisname, nnnames)
      {
        if (strcmp(thisname, conname) == 0)
        {
          conname = NULL;
          break;
        }
      }
    }

    /* and choose a name, if needed */
    if (conname == NULL)
      conname = ChooseConstraintName(RelationGetRelationName(rel),
                       get_attname(RelationGetRelid(rel),
                             cooked->attnum, false),
                       "not_null",
                       RelationGetNamespace(rel),
                       nnnames);
    nnnames = lappend(nnnames, conname);

    /* ignore the origin constraint's is_local and inhcount */
    StoreRelNotNull(rel, conname, cooked->attnum, true,
            false, inhcount, false);

    nncols = lappend_int(nncols, cooked->attnum);
  }

  return nncols;
}

/*
 * Update the count of constraints in the relation's pg_class tuple.
 *
 * Caller had better hold exclusive lock on the relation.
 *
 * An important side effect is that a SI update message will be sent out for
 * the pg_class tuple, which will force other backends to rebuild their
 * relcache entries for the rel.  Also, this backend will rebuild its
 * own relcache entry at the next CommandCounterIncrement.
 */
static void
SetRelationNumChecks(Relation rel, int numchecks)
{
  Relation  relrel;
  HeapTuple reltup;
  Form_pg_class relStruct;

  relrel = table_open(RelationRelationId, RowExclusiveLock);
  reltup = SearchSysCacheCopy1(RELOID,
                 ObjectIdGetDatum(RelationGetRelid(rel)));
  if (!HeapTupleIsValid(reltup))
    elog(ERROR, "cache lookup failed for relation %u",
       RelationGetRelid(rel));
  relStruct = (Form_pg_class) GETSTRUCT(reltup);

  if (relStruct->relchecks != numchecks)
  {
    relStruct->relchecks = numchecks;

    CatalogTupleUpdate(relrel, &reltup->t_self, reltup);
  }
  else
  {
    /* Skip the disk update, but force relcache inval anyway */
    CacheInvalidateRelcache(rel);
  }

  heap_freetuple(reltup);
  table_close(relrel, RowExclusiveLock);
}

/*
 * Check for references to generated columns
 */
static bool
check_nested_generated_walker(Node *node, void *context)
{
  ParseState *pstate = context;

  if (node == NULL)
    return false;
  else if (IsA(node, Var))
  {
    Var      *var = (Var *) node;
    Oid     relid;
    AttrNumber  attnum;

    relid = rt_fetch(var->varno, pstate->p_rtable)->relid;
    if (!OidIsValid(relid))
      return false;   /* XXX shouldn't we raise an error? */

    attnum = var->varattno;

    if (attnum > 0 && get_attgenerated(relid, attnum))
      ereport(ERROR,
          (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
           errmsg("cannot use generated column \"%s\" in column generation expression",
              get_attname(relid, attnum, false)),
           errdetail("A generated column cannot reference another generated column."),
           parser_errposition(pstate, var->location)));
    /* A whole-row Var is necessarily self-referential, so forbid it */
    if (attnum == 0)
      ereport(ERROR,
          (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
           errmsg("cannot use whole-row variable in column generation expression"),
           errdetail("This would cause the generated column to depend on its own value."),
           parser_errposition(pstate, var->location)));
    /* System columns were already checked in the parser */

    return false;
  }
  else
    return expression_tree_walker(node, check_nested_generated_walker,
                    context);
}

static void
check_nested_generated(ParseState *pstate, Node *node)
{
  check_nested_generated_walker(node, pstate);
}

/*
 * Check security of virtual generated column expression.
 *
 * Just like selecting from a view is exploitable (CVE-2024-7348), selecting
 * from a table with virtual generated columns is exploitable.  Users who are
 * concerned about this can avoid selecting from views, but telling them to
 * avoid selecting from tables is less practical.
 *
 * To address this, this restricts generation expressions for virtual
 * generated columns are restricted to using built-in functions and types.  We
 * assume that built-in functions and types cannot be exploited for this
 * purpose.  Note the overall security also requires that all functions in use
 * a immutable.  (For example, there are some built-in non-immutable functions
 * that can run arbitrary SQL.)  The immutability is checked elsewhere, since
 * that is a property that needs to hold independent of security
 * considerations.
 *
 * In the future, this could be expanded by some new mechanism to declare
 * other functions and types as safe or trusted for this purpose, but that is
 * to be designed.
 */

/*
 * Callback for check_functions_in_node() that determines whether a function
 * is user-defined.
 */
static bool
contains_user_functions_checker(Oid func_id, void *context)
{
  return (func_id >= FirstUnpinnedObjectId);
}

/*
 * Checks for all the things we don't want in the generation expressions of
 * virtual generated columns for security reasons.  Errors out if it finds
 * one.
 */
static bool
check_virtual_generated_security_walker(Node *node, void *context)
{
  ParseState *pstate = context;

  if (node == NULL)
    return false;

  if (!IsA(node, List))
  {
    if (check_functions_in_node(node, contains_user_functions_checker, NULL))
      ereport(ERROR,
          errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
          errmsg("generation expression uses user-defined function"),
          errdetail("Virtual generated columns that make use of user-defined functions are not yet supported."),
          parser_errposition(pstate, exprLocation(node)));

    /*
     * check_functions_in_node() doesn't check some node types (see
     * comment there).  We handle CoerceToDomain and MinMaxExpr by
     * checking for built-in types.  The other listed node types cannot
     * call user-definable SQL-visible functions.
     *
     * We furthermore need this type check to handle built-in, immutable
     * polymorphic functions such as array_eq().
     */
    if (exprType(node) >= FirstUnpinnedObjectId)
      ereport(ERROR,
          errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
          errmsg("generation expression uses user-defined type"),
          errdetail("Virtual generated columns that make use of user-defined types are not yet supported."),
          parser_errposition(pstate, exprLocation(node)));
  }

  return expression_tree_walker(node, check_virtual_generated_security_walker, context);
}

static void
check_virtual_generated_security(ParseState *pstate, Node *node)
{
  check_virtual_generated_security_walker(node, pstate);
}

/*
 * Take a raw default and convert it to a cooked format ready for
 * storage.
 *
 * Parse state should be set up to recognize any vars that might appear
 * in the expression.  (Even though we plan to reject vars, it's more
 * user-friendly to give the correct error message than "unknown var".)
 *
 * If atttypid is not InvalidOid, coerce the expression to the specified
 * type (and typmod atttypmod).   attname is only needed in this case:
 * it is used in the error message, if any.
 */
Node *
cookDefault(ParseState *pstate,
      Node *raw_default,
      Oid atttypid,
      int32 atttypmod,
      const char *attname,
      char attgenerated)
{
  Node     *expr;

  Assert(raw_default != NULL);

  /*
   * Transform raw parsetree to executable expression.
   */
  expr = transformExpr(pstate, raw_default, attgenerated ? EXPR_KIND_GENERATED_COLUMN : EXPR_KIND_COLUMN_DEFAULT);

  if (attgenerated)
  {
    /* Disallow refs to other generated columns */
    check_nested_generated(pstate, expr);

    /* Disallow mutable functions */
    if (contain_mutable_functions_after_planning((Expr *) expr))
      ereport(ERROR,
          (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
           errmsg("generation expression is not immutable")));

    /* Check security of expressions for virtual generated column */
    if (attgenerated == ATTRIBUTE_GENERATED_VIRTUAL)
      check_virtual_generated_security(pstate, expr);
  }
  else
  {
    /*
     * For a default expression, transformExpr() should have rejected
     * column references.
     */
    Assert(!contain_var_clause(expr));
  }

  /*
   * Coerce the expression to the correct type and typmod, if given. This
   * should match the parser's processing of non-defaulted expressions ---
   * see transformAssignedExpr().
   */
  if (OidIsValid(atttypid))
  {
    Oid     type_id = exprType(expr);

    expr = coerce_to_target_type(pstate, expr, type_id,
                   atttypid, atttypmod,
                   COERCION_ASSIGNMENT,
                   COERCE_IMPLICIT_CAST,
                   -1);
    if (expr == NULL)
      ereport(ERROR,
          (errcode(ERRCODE_DATATYPE_MISMATCH),
           errmsg("column \"%s\" is of type %s"
              " but default expression is of type %s",
              attname,
              format_type_be(atttypid),
              format_type_be(type_id)),
           errhint("You will need to rewrite or cast the expression.")));
  }

  /*
   * Finally, take care of collations in the finished expression.
   */
  assign_expr_collations(pstate, expr);

  return expr;
}

/*
 * Take a raw CHECK constraint expression and convert it to a cooked format
 * ready for storage.
 *
 * Parse state must be set up to recognize any vars that might appear
 * in the expression.
 */
static Node *
cookConstraint(ParseState *pstate,
         Node *raw_constraint,
         char *relname)
{
  Node     *expr;

  /*
   * Transform raw parsetree to executable expression.
   */
  expr = transformExpr(pstate, raw_constraint, EXPR_KIND_CHECK_CONSTRAINT);

  /*
   * Make sure it yields a boolean result.
   */
  expr = coerce_to_boolean(pstate, expr, "CHECK");

  /*
   * Take care of collations.
   */
  assign_expr_collations(pstate, expr);

  /*
   * Make sure no outside relations are referred to (this is probably dead
   * code now that add_missing_from is history).
   */
  if (list_length(pstate->p_rtable) != 1)
    ereport(ERROR,
        (errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
         errmsg("only table \"%s\" can be referenced in check constraint",
            relname)));

  return expr;
}

/*
 * CopyStatistics --- copy entries in pg_statistic from one rel to another
 */
void
CopyStatistics(Oid fromrelid, Oid torelid)
{
  HeapTuple tup;
  SysScanDesc scan;
  ScanKeyData key[1];
  Relation  statrel;
  CatalogIndexState indstate = NULL;

  statrel = table_open(StatisticRelationId, RowExclusiveLock);

  /* Now search for stat records */
  ScanKeyInit(&key[0],
        Anum_pg_statistic_starelid,
        BTEqualStrategyNumber, F_OIDEQ,
        ObjectIdGetDatum(fromrelid));

  scan = systable_beginscan(statrel, StatisticRelidAttnumInhIndexId,
                true, NULL, 1, key);

  while (HeapTupleIsValid((tup = systable_getnext(scan))))
  {
    Form_pg_statistic statform;

    /* make a modifiable copy */
    tup = heap_copytuple(tup);
    statform = (Form_pg_statistic) GETSTRUCT(tup);

    /* update the copy of the tuple and insert it */
    statform->starelid = torelid;

    /* fetch index information when we know we need it */
    if (indstate == NULL)
      indstate = CatalogOpenIndexes(statrel);

    CatalogTupleInsertWithInfo(statrel, tup, indstate);

    heap_freetuple(tup);
  }

  systable_endscan(scan);

  if (indstate != NULL)
    CatalogCloseIndexes(indstate);
  table_close(statrel, RowExclusiveLock);
}

/*
 * RemoveStatistics --- remove entries in pg_statistic for a rel or column
 *
 * If attnum is zero, remove all entries for rel; else remove only the one(s)
 * for that column.
 */
void
RemoveStatistics(Oid relid, AttrNumber attnum)
{
  Relation  pgstatistic;
  SysScanDesc scan;
  ScanKeyData key[2];
  int     nkeys;
  HeapTuple tuple;

  pgstatistic = table_open(StatisticRelationId, RowExclusiveLock);

  ScanKeyInit(&key[0],
        Anum_pg_statistic_starelid,
        BTEqualStrategyNumber, F_OIDEQ,
        ObjectIdGetDatum(relid));

  if (attnum == 0)
    nkeys = 1;
  else
  {
    ScanKeyInit(&key[1],
          Anum_pg_statistic_staattnum,
          BTEqualStrategyNumber, F_INT2EQ,
          Int16GetDatum(attnum));
    nkeys = 2;
  }

  scan = systable_beginscan(pgstatistic, StatisticRelidAttnumInhIndexId, true,
                NULL, nkeys, key);

  /* we must loop even when attnum != 0, in case of inherited stats */
  while (HeapTupleIsValid(tuple = systable_getnext(scan)))
    CatalogTupleDelete(pgstatistic, &tuple->t_self);

  systable_endscan(scan);

  table_close(pgstatistic, RowExclusiveLock);
}


/*
 * RelationTruncateIndexes - truncate all indexes associated
 * with the heap relation to zero tuples.
 *
 * The routine will truncate and then reconstruct the indexes on
 * the specified relation.  Caller must hold exclusive lock on rel.
 */
static void
RelationTruncateIndexes(Relation heapRelation)
{
  ListCell   *indlist;

  /* Ask the relcache to produce a list of the indexes of the rel */
  foreach(indlist, RelationGetIndexList(heapRelation))
  {
    Oid     indexId = lfirst_oid(indlist);
    Relation  currentIndex;
    IndexInfo  *indexInfo;

    /* Open the index relation; use exclusive lock, just to be sure */
    currentIndex = index_open(indexId, AccessExclusiveLock);

    /*
     * Fetch info needed for index_build.  Since we know there are no
     * tuples that actually need indexing, we can use a dummy IndexInfo.
     * This is slightly cheaper to build, but the real point is to avoid
     * possibly running user-defined code in index expressions or
     * predicates.  We might be getting invoked during ON COMMIT
     * processing, and we don't want to run any such code then.
     */
    indexInfo = BuildDummyIndexInfo(currentIndex);

    /*
     * Now truncate the actual file (and discard buffers).
     */
    RelationTruncate(currentIndex, 0);

    /* Initialize the index and rebuild */
    /* Note: we do not need to re-establish pkey setting */
    index_build(heapRelation, currentIndex, indexInfo, true, false);

    /* We're done with this index */
    index_close(currentIndex, NoLock);
  }
}

/*
 *   heap_truncate
 *
 *   This routine deletes all data within all the specified relations.
 *
 * This is not transaction-safe!  There is another, transaction-safe
 * implementation in commands/tablecmds.c.  We now use this only for
 * ON COMMIT truncation of temporary tables, where it doesn't matter.
 */
void
heap_truncate(List *relids)
{
  List     *relations = NIL;
  ListCell   *cell;

  /* Open relations for processing, and grab exclusive access on each */
  foreach(cell, relids)
  {
    Oid     rid = lfirst_oid(cell);
    Relation  rel;

    rel = table_open(rid, AccessExclusiveLock);
    relations = lappend(relations, rel);
  }

  /* Don't allow truncate on tables that are referenced by foreign keys */
  heap_truncate_check_FKs(relations, true);

  /* OK to do it */
  foreach(cell, relations)
  {
    Relation  rel = lfirst(cell);

    /* Truncate the relation */
    heap_truncate_one_rel(rel);

    /* Close the relation, but keep exclusive lock on it until commit */
    table_close(rel, NoLock);
  }
}

/*
 *   heap_truncate_one_rel
 *
 *   This routine deletes all data within the specified relation.
 *
 * This is not transaction-safe, because the truncation is done immediately
 * and cannot be rolled back later.  Caller is responsible for having
 * checked permissions etc, and must have obtained AccessExclusiveLock.
 */
void
heap_truncate_one_rel(Relation rel)
{
  Oid     toastrelid;

  /*
   * Truncate the relation.  Partitioned tables have no storage, so there is
   * nothing to do for them here.
   */
  if (rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
    return;

  /* Truncate the underlying relation */
  table_relation_nontransactional_truncate(rel);

  /* If the relation has indexes, truncate the indexes too */
  RelationTruncateIndexes(rel);

  /* If there is a toast table, truncate that too */
  toastrelid = rel->rd_rel->reltoastrelid;
  if (OidIsValid(toastrelid))
  {
    Relation  toastrel = table_open(toastrelid, AccessExclusiveLock);

    table_relation_nontransactional_truncate(toastrel);
    RelationTruncateIndexes(toastrel);
    /* keep the lock... */
    table_close(toastrel, NoLock);
  }
}

/*
 * heap_truncate_check_FKs
 *    Check for foreign keys referencing a list of relations that
 *    are to be truncated, and raise error if there are any
 *
 * We disallow such FKs (except self-referential ones) since the whole point
 * of TRUNCATE is to not scan the individual rows to be thrown away.
 *
 * This is split out so it can be shared by both implementations of truncate.
 * Caller should already hold a suitable lock on the relations.
 *
 * tempTables is only used to select an appropriate error message.
 */
void
heap_truncate_check_FKs(List *relations, bool tempTables)
{
  List     *oids = NIL;
  List     *dependents;
  ListCell   *cell;

  /*
   * Build a list of OIDs of the interesting relations.
   *
   * If a relation has no triggers, then it can neither have FKs nor be
   * referenced by a FK from another table, so we can ignore it.  For
   * partitioned tables, FKs have no triggers, so we must include them
   * anyway.
   */
  foreach(cell, relations)
  {
    Relation  rel = lfirst(cell);

    if (rel->rd_rel->relhastriggers ||
      rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
      oids = lappend_oid(oids, RelationGetRelid(rel));
  }

  /*
   * Fast path: if no relation has triggers, none has FKs either.
   */
  if (oids == NIL)
    return;

  /*
   * Otherwise, must scan pg_constraint.  We make one pass with all the
   * relations considered; if this finds nothing, then all is well.
   */
  dependents = heap_truncate_find_FKs(oids);
  if (dependents == NIL)
    return;

  /*
   * Otherwise we repeat the scan once per relation to identify a particular
   * pair of relations to complain about.  This is pretty slow, but
   * performance shouldn't matter much in a failure path.  The reason for
   * doing things this way is to ensure that the message produced is not
   * dependent on chance row locations within pg_constraint.
   */
  foreach(cell, oids)
  {
    Oid     relid = lfirst_oid(cell);
    ListCell   *cell2;

    dependents = heap_truncate_find_FKs(list_make1_oid(relid));

    foreach(cell2, dependents)
    {
      Oid     relid2 = lfirst_oid(cell2);

      if (!list_member_oid(oids, relid2))
      {
        char     *relname = get_rel_name(relid);
        char     *relname2 = get_rel_name(relid2);

        if (tempTables)
          ereport(ERROR,
              (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
               errmsg("unsupported ON COMMIT and foreign key combination"),
               errdetail("Table \"%s\" references \"%s\", but they do not have the same ON COMMIT setting.",
                     relname2, relname)));
        else
          ereport(ERROR,
              (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
               errmsg("cannot truncate a table referenced in a foreign key constraint"),
               errdetail("Table \"%s\" references \"%s\".",
                     relname2, relname),
               errhint("Truncate table \"%s\" at the same time, "
                   "or use TRUNCATE ... CASCADE.",
                   relname2)));
      }
    }
  }
}

/*
 * heap_truncate_find_FKs
 *    Find relations having foreign keys referencing any of the given rels
 *
 * Input and result are both lists of relation OIDs.  The result contains
 * no duplicates, does *not* include any rels that were already in the input
 * list, and is sorted in OID order.  (The last property is enforced mainly
 * to guarantee consistent behavior in the regression tests; we don't want
 * behavior to change depending on chance locations of rows in pg_constraint.)
 *
 * Note: caller should already have appropriate lock on all rels mentioned
 * in relationIds.  Since adding or dropping an FK requires exclusive lock
 * on both rels, this ensures that the answer will be stable.
 */
List *
heap_truncate_find_FKs(List *relationIds)
{
  List     *result = NIL;
  List     *oids;
  List     *parent_cons;
  ListCell   *cell;
  ScanKeyData key;
  Relation  fkeyRel;
  SysScanDesc fkeyScan;
  HeapTuple tuple;
  bool    restart;

  oids = list_copy(relationIds);

  /*
   * Must scan pg_constraint.  Right now, it is a seqscan because there is
   * no available index on confrelid.
   */
  fkeyRel = table_open(ConstraintRelationId, AccessShareLock);

restart:
  restart = false;
  parent_cons = NIL;

  fkeyScan = systable_beginscan(fkeyRel, InvalidOid, false,
                  NULL, 0, NULL);

  while (HeapTupleIsValid(tuple = systable_getnext(fkeyScan)))
  {
    Form_pg_constraint con = (Form_pg_constraint) GETSTRUCT(tuple);

    /* Not a foreign key */
    if (con->contype != CONSTRAINT_FOREIGN)
      continue;

    /* Not referencing one of our list of tables */
    if (!list_member_oid(oids, con->confrelid))
      continue;

    /*
     * If this constraint has a parent constraint which we have not seen
     * yet, keep track of it for the second loop, below.  Tracking parent
     * constraints allows us to climb up to the top-level constraint and
     * look for all possible relations referencing the partitioned table.
     */
    if (OidIsValid(con->conparentid) &&
      !list_member_oid(parent_cons, con->conparentid))
      parent_cons = lappend_oid(parent_cons, con->conparentid);

    /*
     * Add referencer to result, unless present in input list.  (Don't
     * worry about dupes: we'll fix that below).
     */
    if (!list_member_oid(relationIds, con->conrelid))
      result = lappend_oid(result, con->conrelid);
  }

  systable_endscan(fkeyScan);

  /*
   * Process each parent constraint we found to add the list of referenced
   * relations by them to the oids list.  If we do add any new such
   * relations, redo the first loop above.  Also, if we see that the parent
   * constraint in turn has a parent, add that so that we process all
   * relations in a single additional pass.
   */
  foreach(cell, parent_cons)
  {
    Oid     parent = lfirst_oid(cell);

    ScanKeyInit(&key,
          Anum_pg_constraint_oid,
          BTEqualStrategyNumber, F_OIDEQ,
          ObjectIdGetDatum(parent));

    fkeyScan = systable_beginscan(fkeyRel, ConstraintOidIndexId,
                    true, NULL, 1, &key);

    tuple = systable_getnext(fkeyScan);
    if (HeapTupleIsValid(tuple))
    {
      Form_pg_constraint con = (Form_pg_constraint) GETSTRUCT(tuple);

      /*
       * pg_constraint rows always appear for partitioned hierarchies
       * this way: on the each side of the constraint, one row appears
       * for each partition that points to the top-most table on the
       * other side.
       *
       * Because of this arrangement, we can correctly catch all
       * relevant relations by adding to 'parent_cons' all rows with
       * valid conparentid, and to the 'oids' list all rows with a zero
       * conparentid.  If any oids are added to 'oids', redo the first
       * loop above by setting 'restart'.
       */
      if (OidIsValid(con->conparentid))
        parent_cons = list_append_unique_oid(parent_cons,
                           con->conparentid);
      else if (!list_member_oid(oids, con->confrelid))
      {
        oids = lappend_oid(oids, con->confrelid);
        restart = true;
      }
    }

    systable_endscan(fkeyScan);
  }

  list_free(parent_cons);
  if (restart)
    goto restart;

  table_close(fkeyRel, AccessShareLock);
  list_free(oids);

  /* Now sort and de-duplicate the result list */
  list_sort(result, list_oid_cmp);
  list_deduplicate_oid(result);

  return result;
}

/*
 * StorePartitionKey
 *    Store information about the partition key rel into the catalog
 */
void
StorePartitionKey(Relation rel,
          char strategy,
          int16 partnatts,
          AttrNumber *partattrs,
          List *partexprs,
          Oid *partopclass,
          Oid *partcollation)
{
  int     i;
  int2vector *partattrs_vec;
  oidvector  *partopclass_vec;
  oidvector  *partcollation_vec;
  Datum   partexprDatum;
  Relation  pg_partitioned_table;
  HeapTuple tuple;
  Datum   values[Natts_pg_partitioned_table];
  bool    nulls[Natts_pg_partitioned_table] = {0};
  ObjectAddress myself;
  ObjectAddress referenced;
  ObjectAddresses *addrs;

  Assert(rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE);

  /* Copy the partition attribute numbers, opclass OIDs into arrays */
  partattrs_vec = buildint2vector(partattrs, partnatts);
  partopclass_vec = buildoidvector(partopclass, partnatts);
  partcollation_vec = buildoidvector(partcollation, partnatts);

  /* Convert the expressions (if any) to a text datum */
  if (partexprs)
  {
    char     *exprString;

    exprString = nodeToString(partexprs);
    partexprDatum = CStringGetTextDatum(exprString);
    pfree(exprString);
  }
  else
    partexprDatum = (Datum) 0;

  pg_partitioned_table = table_open(PartitionedRelationId, RowExclusiveLock);

  /* Only this can ever be NULL */
  if (!partexprDatum)
    nulls[Anum_pg_partitioned_table_partexprs - 1] = true;

  values[Anum_pg_partitioned_table_partrelid - 1] = ObjectIdGetDatum(RelationGetRelid(rel));
  values[Anum_pg_partitioned_table_partstrat - 1] = CharGetDatum(strategy);
  values[Anum_pg_partitioned_table_partnatts - 1] = Int16GetDatum(partnatts);
  values[Anum_pg_partitioned_table_partdefid - 1] = ObjectIdGetDatum(InvalidOid);
  values[Anum_pg_partitioned_table_partattrs - 1] = PointerGetDatum(partattrs_vec);
  values[Anum_pg_partitioned_table_partclass - 1] = PointerGetDatum(partopclass_vec);
  values[Anum_pg_partitioned_table_partcollation - 1] = PointerGetDatum(partcollation_vec);
  values[Anum_pg_partitioned_table_partexprs - 1] = partexprDatum;

  tuple = heap_form_tuple(RelationGetDescr(pg_partitioned_table), values, nulls);

  CatalogTupleInsert(pg_partitioned_table, tuple);
  table_close(pg_partitioned_table, RowExclusiveLock);

  /* Mark this relation as dependent on a few things as follows */
  addrs = new_object_addresses();
  ObjectAddressSet(myself, RelationRelationId, RelationGetRelid(rel));

  /* Operator class and collation per key column */
  for (i = 0; i < partnatts; i++)
  {
    ObjectAddressSet(referenced, OperatorClassRelationId, partopclass[i]);
    add_exact_object_address(&referenced, addrs);

    /* The default collation is pinned, so don't bother recording it */
    if (OidIsValid(partcollation[i]) &&
      partcollation[i] != DEFAULT_COLLATION_OID)
    {
      ObjectAddressSet(referenced, CollationRelationId, partcollation[i]);
      add_exact_object_address(&referenced, addrs);
    }
  }

  record_object_address_dependencies(&myself, addrs, DEPENDENCY_NORMAL);
  free_object_addresses(addrs);

  /*
   * The partitioning columns are made internally dependent on the table,
   * because we cannot drop any of them without dropping the whole table.
   * (ATExecDropColumn independently enforces that, but it's not bulletproof
   * so we need the dependencies too.)
   */
  for (i = 0; i < partnatts; i++)
  {
    if (partattrs[i] == 0)
      continue;     /* ignore expressions here */

    ObjectAddressSubSet(referenced, RelationRelationId,
              RelationGetRelid(rel), partattrs[i]);
    recordDependencyOn(&referenced, &myself, DEPENDENCY_INTERNAL);
  }

  /*
   * Also consider anything mentioned in partition expressions.  External
   * references (e.g. functions) get NORMAL dependencies.  Table columns
   * mentioned in the expressions are handled the same as plain partitioning
   * columns, i.e. they become internally dependent on the whole table.
   */
  if (partexprs)
    recordDependencyOnSingleRelExpr(&myself,
                    (Node *) partexprs,
                    RelationGetRelid(rel),
                    DEPENDENCY_NORMAL,
                    DEPENDENCY_INTERNAL,
                    true /* reverse the self-deps */ );

  /*
   * We must invalidate the relcache so that the next
   * CommandCounterIncrement() will cause the same to be rebuilt using the
   * information in just created catalog entry.
   */
  CacheInvalidateRelcache(rel);
}

/*
 *  RemovePartitionKeyByRelId
 *    Remove pg_partitioned_table entry for a relation
 */
void
RemovePartitionKeyByRelId(Oid relid)
{
  Relation  rel;
  HeapTuple tuple;

  rel = table_open(PartitionedRelationId, RowExclusiveLock);

  tuple = SearchSysCache1(PARTRELID, ObjectIdGetDatum(relid));
  if (!HeapTupleIsValid(tuple))
    elog(ERROR, "cache lookup failed for partition key of relation %u",
       relid);

  CatalogTupleDelete(rel, &tuple->t_self);

  ReleaseSysCache(tuple);
  table_close(rel, RowExclusiveLock);
}

/*
 * StorePartitionBound
 *    Update pg_class tuple of rel to store the partition bound and set
 *    relispartition to true
 *
 * If this is the default partition, also update the default partition OID in
 * pg_partitioned_table.
 *
 * Also, invalidate the parent's relcache, so that the next rebuild will load
 * the new partition's info into its partition descriptor.  If there is a
 * default partition, we must invalidate its relcache entry as well.
 */
void
StorePartitionBound(Relation rel, Relation parent, PartitionBoundSpec *bound)
{
  Relation  classRel;
  HeapTuple tuple,
        newtuple;
  Datum   new_val[Natts_pg_class];
  bool    new_null[Natts_pg_class],
        new_repl[Natts_pg_class];
  Oid     defaultPartOid;

  /* Update pg_class tuple */
  classRel = table_open(RelationRelationId, RowExclusiveLock);
  tuple = SearchSysCacheCopy1(RELOID,
                ObjectIdGetDatum(RelationGetRelid(rel)));
  if (!HeapTupleIsValid(tuple))
    elog(ERROR, "cache lookup failed for relation %u",
       RelationGetRelid(rel));

#ifdef USE_ASSERT_CHECKING
  {
    Form_pg_class classForm;
    bool    isnull;

    classForm = (Form_pg_class) GETSTRUCT(tuple);
    Assert(!classForm->relispartition);
    (void) SysCacheGetAttr(RELOID, tuple, Anum_pg_class_relpartbound,
                 &isnull);
    Assert(isnull);
  }
#endif

  /* Fill in relpartbound value */
  memset(new_val, 0, sizeof(new_val));
  memset(new_null, false, sizeof(new_null));
  memset(new_repl, false, sizeof(new_repl));
  new_val[Anum_pg_class_relpartbound - 1] = CStringGetTextDatum(nodeToString(bound));
  new_null[Anum_pg_class_relpartbound - 1] = false;
  new_repl[Anum_pg_class_relpartbound - 1] = true;
  newtuple = heap_modify_tuple(tuple, RelationGetDescr(classRel),
                 new_val, new_null, new_repl);
  /* Also set the flag */
  ((Form_pg_class) GETSTRUCT(newtuple))->relispartition = true;

  /*
   * We already checked for no inheritance children, but reset
   * relhassubclass in case it was left over.
   */
  if (rel->rd_rel->relkind == RELKIND_RELATION && rel->rd_rel->relhassubclass)
    ((Form_pg_class) GETSTRUCT(newtuple))->relhassubclass = false;

  CatalogTupleUpdate(classRel, &newtuple->t_self, newtuple);
  heap_freetuple(newtuple);
  table_close(classRel, RowExclusiveLock);

  /*
   * If we're storing bounds for the default partition, update
   * pg_partitioned_table too.
   */
  if (bound->is_default)
    update_default_partition_oid(RelationGetRelid(parent),
                   RelationGetRelid(rel));

  /* Make these updates visible */
  CommandCounterIncrement();

  /*
   * The partition constraint for the default partition depends on the
   * partition bounds of every other partition, so we must invalidate the
   * relcache entry for that partition every time a partition is added or
   * removed.
   */
  defaultPartOid =
    get_default_oid_from_partdesc(RelationGetPartitionDesc(parent, true));
  if (OidIsValid(defaultPartOid))
    CacheInvalidateRelcacheByRelid(defaultPartOid);

  CacheInvalidateRelcache(parent);
}

Coverage Report

Created: 2025-10-09 06:07