| Документация по PostgreSQL 9.1.1 | ||||
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The catalog pg_operator stores information about operators. See CREATE OPERATOR and Section 35.12 for more information.
Table 45-32. pg_operator Columns
| Name | Type | References | Description |
|---|---|---|---|
| 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.