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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 functions are compatible with the family's semantics, but are not required for correct  function-
       ing of any specific index. (Operators and functions that are so required should be declared as part of an oper-
       ator class, instead; see CREATE OPERATOR CLASS [create_operator_class(7)].)  PostgreSQL will allow  loose  mem-
       bers  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 support 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 opera-
       tors 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  speci-
              fied.

       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 func-
       tion or operator in an operator family is tantamount to granting public execute permission on it. This is  usu-
       ally 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         2014-02-17          ALTER OPERATOR FAMILY(7)