ALTER OPERATOR (original) (raw)

ALTER OPERATOR — change the definition of an operator

Synopsis

ALTER OPERATOR name ( { lefttype | NONE } , righttype ) OWNER TO { newowner | CURRENT_ROLE | CURRENT_USER | SESSION_USER }

ALTER OPERATOR name ( { lefttype | NONE } , righttype ) SET SCHEMA newschema

ALTER OPERATOR name ( { lefttype | NONE } , righttype ) SET ( { RESTRICT = { resproc | NONE } | JOIN = { joinproc | NONE } | COMMUTATOR = comop | NEGATOR = negop | HASHES | MERGES } [, ... ] )

Description

ALTER OPERATOR changes the definition of an operator.

You must own the operator to use ALTER OPERATOR. To alter the owner, you must be able to SET ROLE to the new owning role, and that role must have CREATE privilege on the operator's schema. (These restrictions enforce that altering the owner doesn't do anything you couldn't do by dropping and recreating the operator. However, a superuser can alter ownership of any operator anyway.)

Parameters

name

The name (optionally schema-qualified) of an existing operator.

lefttype

The data type of the operator's left operand; write NONE if the operator has no left operand.

righttype

The data type of the operator's right operand.

newowner

The new owner of the operator.

newschema

The new schema for the operator.

resproc

The restriction selectivity estimator function for this operator; write NONE to remove existing selectivity estimator.

joinproc

The join selectivity estimator function for this operator; write NONE to remove existing selectivity estimator.

comop

The commutator of this operator. Can only be changed if the operator does not have an existing commutator.

negop

The negator of this operator. Can only be changed if the operator does not have an existing negator.

HASHES

Indicates this operator can support a hash join. Can only be enabled and not disabled.

MERGES

Indicates this operator can support a merge join. Can only be enabled and not disabled.

Notes

Refer to Section 36.14 and Section 36.15 for further information.

Since commutators come in pairs that are commutators of each other, ALTER OPERATOR SET COMMUTATOR will also set the commutator of the comop to be the target operator. Likewise, ALTER OPERATOR SET NEGATOR will also set the negator of the negop to be the target operator. Therefore, you must own the commutator or negator operator as well as the target operator.

Examples

Change the owner of a custom operator a @@ b for type text:

ALTER OPERATOR @@ (text, text) OWNER TO joe;

Change the restriction and join selectivity estimator functions of a custom operator a && b for type int[]:

ALTER OPERATOR && (int[], int[]) SET (RESTRICT = _int_contsel, JOIN = _int_contjoinsel);

Mark the && operator as being its own commutator:

ALTER OPERATOR && (int[], int[]) SET (COMMUTATOR = &&);

Compatibility

There is no ALTER OPERATOR statement in the SQL standard.