---
title: "pg_operator"
source: https://cloudberry.apache.org/docs/sys-catalogs/sys-tables/pg-operator
---

# pg_operator

The `pg_operator` system catalog table stores information about operators, both built-in and those defined by `CREATE OPERATOR`. Unused column contain zeroes. For example, `oprleft` is zero for a prefix operator.

|column|type|references|description|
|------|----|----------|-----------|
|`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`|boolean| |This operator supports merge joins|
|`oprcanhash`|boolean| |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|