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NAMEALTER_OPERATOR - change the definition of an operator SYNOPSISALTER OPERATOR name ( { left_type | NONE } , right_type )
DESCRIPTIONALTER 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.) PARAMETERSname 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.
NOTESRefer 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. EXAMPLESChange 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 = &&); COMPATIBILITYThere is no ALTER OPERATOR statement in the SQL standard. SEE ALSOCREATE OPERATOR (CREATE_OPERATOR(7)), DROP OPERATOR (DROP_OPERATOR(7))
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