ALTER OPERATOR
ALTER OPERATOR
7
SQL - Language Statements
ALTER OPERATOR
change the definition of an operator
ALTER OPERATOR name ( { left_type | NONE } , right_type )
OWNER TO { new_owner | CURRENT_ROLE | CURRENT_USER | SESSION_USER }
ALTER OPERATOR name ( { left_type | NONE } , right_type )
SET SCHEMA new_schema
ALTER OPERATOR name ( { 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 and
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.
See Also