ALTER OPERATOR
ALTER OPERATOR — change the definition of an operator
Synopsis
ALTER OPERATORname
( {left_type
| NONE } ,right_type
) OWNER TO {new_owner
| CURRENT_ROLE | CURRENT_USER | SESSION_USER } ALTER OPERATORname
( {left_type
| NONE } ,right_type
) SET SCHEMAnew_schema
ALTER OPERATORname
( {left_type
| NONE } ,right_type
) SET ( { RESTRICT = {res_proc
| NONE } | JOIN = {join_proc
| NONE } | COMMUTATOR =com_op
| NEGATOR =neg_op
| 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.
left_type
The data type of the operator's left operand; write
NONE
if the operator has no left operand.right_type
The data type of the operator's right operand.
new_owner
The new owner of the operator.
new_schema
The new schema for the operator.
res_proc
The restriction selectivity estimator function for this operator; write NONE to remove existing selectivity estimator.
join_proc
The join selectivity estimator function for this operator; write NONE to remove existing selectivity estimator.
com_op
The commutator of this operator. Can only be changed if the operator does not have an existing commutator.
neg_op
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 com_op
to be the target operator. Likewise, ALTER OPERATOR SET NEGATOR
will also set the negator of the neg_op
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.