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The field type of value and field do not need to match to be considered equal, but not all comparisons are possible. EQUAL_TO and NOT_EQUAL_TO attempt to compare even with incompatible types, but all other comparisons are invalid with incompatible types. A value of type: - string can be compared against all other types - boolean can only be compared against other booleans - integer can be compared against doubles or a string if the string value can be parsed as an integer. - double can be compared against integers or a string if the string can be parsed as a double. - Timestamp can be compared against strings in RFC 3339 date string format. - TimeOfDay can be compared against timestamps and strings in the format of 'HH:mm:ss'. If we fail to compare do to type mismatch, a warning will be given and the condition will evaluate to false.