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.

Table 1. pg_catalog.pg_operator

column	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)
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		pg_operator.oid	Negator of this operator, if any.
oprlsortop	oid	pg_operator.oid	If this operator supports merge joins, the operator that sorts the type of the left-hand operand (L<L).
oprrsortop	oid	pg_operator.oid	If this operator supports merge joins, the operator that sorts the type of the right-hand operand (R<R).
oprltcmpop	oid	pg_operator.oid	If this operator supports merge joins, the less-than operator that compares the left and right operand types (L<R).
oprgtcmpop	oid	pg_operator.oid	If this operator supports merge joins, the greater-than operator that compares the left and right operand types (L>R).
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.