Postgres-XC 1.2devel Documentation | ||||
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Note: The following description applies both to Postgres-XC and PostgreSQL if not described explicitly. You can read PostgreSQL as Postgres-XC except for version number, which is specific to each product.
The catalog pg_operator stores information about operators. See CREATE OPERATOR and Section 34.12 for more information.
Table 47-33. pg_operator Columns
Name | Type | References | Description |
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oid | oid | Row identifier (hidden attribute; must be explicitly selected) | |
oprname | name | Name of the operator | |
oprnamespace | oid | pg_namespace.oid | The OID of the namespace that contains this operator |
oprowner | oid | pg_authid.oid | Owner of the operator |
oprkind | char | b = infix ("both"), l = prefix ("left"), r = postfix ("right") | |
oprcanmerge | bool | This operator supports merge joins | |
oprcanhash | bool | This operator supports hash joins | |
oprleft | oid | pg_type.oid | Type of the left operand |
oprright | oid | pg_type.oid | Type of the right operand |
oprresult | oid | pg_type.oid | Type of the result |
oprcom | oid | pg_operator.oid | Commutator of this operator, if any |
oprnegate | oid | pg_operator.oid | Negator of this operator, if any |
oprcode | regproc | pg_proc.oid | Function that implements this operator |
oprrest | regproc | pg_proc.oid | Restriction selectivity estimation function for this operator |
oprjoin | regproc | pg_proc.oid | Join selectivity estimation function for this operator |
Unused column contain zeroes. For example, oprleft is zero for a prefix operator.