ALTER OPERATOR FAMILY(7)                                  SQL Commands                                  ALTER OPERATOR FAMILY(7)



NAME
       ALTER OPERATOR FAMILY - change the definition of an operator family


SYNOPSIS
       ALTER OPERATOR FAMILY name USING index_method ADD
         {  OPERATOR strategy_number operator_name ( op_type, op_type )
          | FUNCTION support_number [ ( op_type [ , op_type ] ) ] funcname ( argument_type [, ...] )
         } [, ... ]
       ALTER OPERATOR FAMILY name USING index_method DROP
         {  OPERATOR strategy_number ( op_type [ , op_type ] )
          | FUNCTION support_number ( op_type [ , op_type ] )
         } [, ... ]
       ALTER OPERATOR FAMILY name USING index_method RENAME TO newname
       ALTER OPERATOR FAMILY name USING index_method OWNER TO newowner


DESCRIPTION
       ALTER  OPERATOR  FAMILY  changes the definition of an operator family. You can add operators and support functions to the
       family, remove them from the family, or change the family's name or owner.

       When operators and support functions are added to a family with ALTER OPERATOR FAMILY, they are not part of any  specific
       operator class within the family, but are just ``loose'' within the family. This indicates that these operators and func-
       tions are compatible with the family's semantics, but are not required for correct functioning  of  any  specific  index.
       (Operators and functions that are so required should be declared as part of an operator class, instead; see CREATE OPERA-
       TOR CLASS [create_operator_class(7)].)  PostgreSQL will allow loose members of a family to be dropped from the family  at
       any time, but members of an operator class cannot be dropped without dropping the whole class and any indexes that depend
       on it.  Typically, single-data-type operators and functions are part of operator classes because they are needed to  sup-
       port  an  index  on  that specific data type, while cross-data-type operators and functions are made loose members of the
       family.

       You must be a superuser to use ALTER OPERATOR FAMILY.  (This restriction is made because  an  erroneous  operator  family
       definition could confuse or even crash the server.)

       ALTER  OPERATOR  FAMILY  does  not  presently check whether the operator family definition includes all the operators and
       functions required by the index method, nor whether the operators and functions form a self-consistent  set.  It  is  the
       user's responsibility to define a valid operator family.

       Refer to in the documentation for further information.

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

       index_method
              The name of the index method this operator family is for.

       strategy_number
              The index method's strategy number for an operator associated with the operator family.

       operator_name
              The name (optionally schema-qualified) of an operator associated with the operator family.

       op_type
              In  an  OPERATOR  clause, the operand data type(s) of the operator, or NONE to signify a left-unary or right-unary
              operator. Unlike the comparable syntax in CREATE OPERATOR CLASS, the operand data types must always be specified.

              In an ADD FUNCTION clause, the operand data type(s) the function is intended to support,  if  different  from  the
              input  data  type(s) of the function. For B-tree and hash indexes it is not necessary to specify op_type since the
              function's input data type(s) are always the correct ones to use. For GIN and GiST  indexes  it  is  necessary  to
              specify the input data type the function is to be used with.

              In a DROP FUNCTION clause, the operand data type(s) the function is intended to support must be specified.

       support_number
              The index method's support procedure number for a function associated with the operator family.

       funcname
              The  name  (optionally  schema-qualified) of a function that is an index method support procedure for the operator
              family.

       argument_types
              The parameter data type(s) of the function.

       newname
              The new name of the operator family.

       newowner
              The new owner of the operator family.

       The OPERATOR and FUNCTION clauses can appear in any order.

NOTES
       Notice that the DROP syntax only specifies the ``slot'' in the operator family, by strategy or support number  and  input
       data  type(s).  The  name  of  the  operator or function occupying the slot is not mentioned. Also, for DROP FUNCTION the
       type(s) to specify are the input data type(s) the function is intended to support; for GIN and GiST  indexes  this  might
       have nothing to do with the actual input argument types of the function.

       Because  the  index  machinery  does not check access permissions on functions before using them, including a function or
       operator in an operator family is tantamount to granting public execute permission on it. This is usually  not  an  issue
       for the sorts of functions that are useful in an operator family.

       The  operators  should  not  be  defined by SQL functions. A SQL function is likely to be inlined into the calling query,
       which will prevent the optimizer from recognizing that the query matches an index.

       Before PostgreSQL 8.4, the OPERATOR clause could include a RECHECK option. This is no longer supported because whether an
       index  operator  is  ``lossy''  is now determined on-the-fly at runtime. This allows efficient handling of cases where an
       operator might or might not be lossy.

EXAMPLES
       The following example command adds cross-data-type operators and support functions to an  operator  family  that  already
       contains B-tree operator classes for data types int4 and int2.

       ALTER OPERATOR FAMILY integer_ops USING btree ADD

         -- int4 vs int2
         OPERATOR 1 < (int4, int2) ,
         OPERATOR 2 <= (int4, int2) ,
         OPERATOR 3 = (int4, int2) ,
         OPERATOR 4 >= (int4, int2) ,
         OPERATOR 5 > (int4, int2) ,
         FUNCTION 1 btint42cmp(int4, int2) ,

         -- int2 vs int4
         OPERATOR 1 < (int2, int4) ,
         OPERATOR 2 <= (int2, int4) ,
         OPERATOR 3 = (int2, int4) ,
         OPERATOR 4 >= (int2, int4) ,
         OPERATOR 5 > (int2, int4) ,
         FUNCTION 1 btint24cmp(int2, int4) ;


       To remove these entries again:

       ALTER OPERATOR FAMILY integer_ops USING btree DROP

         -- int4 vs int2
         OPERATOR 1 (int4, int2) ,
         OPERATOR 2 (int4, int2) ,
         OPERATOR 3 (int4, int2) ,
         OPERATOR 4 (int4, int2) ,
         OPERATOR 5 (int4, int2) ,
         FUNCTION 1 (int4, int2) ,

         -- int2 vs int4
         OPERATOR 1 (int2, int4) ,
         OPERATOR 2 (int2, int4) ,
         OPERATOR 3 (int2, int4) ,
         OPERATOR 4 (int2, int4) ,
         OPERATOR 5 (int2, int4) ,
         FUNCTION 1 (int2, int4) ;


COMPATIBILITY
       There is no ALTER OPERATOR FAMILY statement in the SQL standard.

SEE ALSO
       CREATE OPERATOR FAMILY [create_operator_family(7)], DROP OPERATOR FAMILY [drop_operator_family(7)], CREATE OPERATOR CLASS
       [create_operator_class(7)], ALTER OPERATOR CLASS [alter_operator_class(7)], DROP OPERATOR CLASS [drop_operator_class(7)]



SQL - Language Statements                                  2011-09-22                                   ALTER OPERATOR FAMILY(7)