phpman > man > CREATE_OPERATOR_CLASS(7)

CREATE OPERATOR CLASS(7)           PostgreSQL 14.23 Documentation           CREATE OPERATOR CLASS(7)



NAME
       CREATE_OPERATOR_CLASS - define a new operator class

SYNOPSIS
       CREATE OPERATOR CLASS name [ DEFAULT ] FOR TYPE data_type
         USING index_method [ FAMILY family_name ] AS
         {  OPERATOR strategy_number operator_name [ ( op_type, op_type ) ] [ FOR SEARCH | FOR ORDER BY sort_family_name ]
          | FUNCTION support_number [ ( op_type [ , op_type ] ) ] function_name ( argument_type [, ...] )
          | STORAGE storage_type
         } [, ... ]

DESCRIPTION
       CREATE OPERATOR CLASS creates a new operator class. An operator class defines how a
       particular data type can be used with an index. The operator class specifies that certain
       operators will fill particular roles or “strategies” for this data type and this index
       method. The operator class also specifies the support functions to be used by the index
       method when the operator class is selected for an index column. All the operators and
       functions used by an operator class must be defined before the operator class can be created.

       If a schema name is given then the operator class is created in the specified schema.
       Otherwise it is created in the current schema. Two operator classes in the same schema can
       have the same name only if they are for different index methods.

       The user who defines an operator class becomes its owner. Presently, the creating user must
       be a superuser. (This restriction is made because an erroneous operator class definition
       could confuse or even crash the server.)

       CREATE OPERATOR CLASS does not presently check whether the operator class 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 class.

       Related operator classes can be grouped into operator families. To add a new operator class
       to an existing family, specify the FAMILY option in CREATE OPERATOR CLASS. Without this
       option, the new class is placed into a family named the same as the new class (creating that
       family if it doesn't already exist).

       Refer to Section 38.16 for further information.

PARAMETERS
       name
           The name of the operator class to be created. The name can be schema-qualified.

       DEFAULT
           If present, the operator class will become the default operator class for its data type.
           At most one operator class can be the default for a specific data type and index method.

       data_type
           The column data type that this operator class is for.

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

       family_name
           The name of the existing operator family to add this operator class to. If not specified,
           a family named the same as the operator class is used (creating it, if it doesn't already
           exist).

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

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

       op_type
           In an OPERATOR clause, the operand data type(s) of the operator, or NONE to signify a
           prefix operator. The operand data types can be omitted in the normal case where they are
           the same as the operator class's data type.

           In a 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 comparison functions
           and hash functions) or the class's data type (for B-tree sort support functions, B-tree
           equal image functions, and all functions in GiST, SP-GiST, GIN and BRIN operator
           classes). These defaults are correct, and so op_type need not be specified in FUNCTION
           clauses, except for the case of a B-tree sort support function that is meant to support
           cross-data-type comparisons.

       sort_family_name
           The name (optionally schema-qualified) of an existing btree operator family that
           describes the sort ordering associated with an ordering operator.

           If neither FOR SEARCH nor FOR ORDER BY is specified, FOR SEARCH is the default.

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

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

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

       storage_type
           The data type actually stored in the index. Normally this is the same as the column data
           type, but some index methods (currently GiST, GIN, SP-GiST and BRIN) allow it to be
           different. The STORAGE clause must be omitted unless the index method allows a different
           type to be used. If the column data_type is specified as anyarray, the storage_type can
           be declared as anyelement to indicate that the index entries are members of the element
           type belonging to the actual array type that each particular index is created for.

       The OPERATOR, FUNCTION, and STORAGE clauses can appear in any order.

NOTES
       Because the index machinery does not check access permissions on functions before using them,
       including a function or operator in an operator class 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 class.

       The operators should not be defined by SQL functions. An 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 run
       time. This allows efficient handling of cases where an operator might or might not be lossy.

EXAMPLES
       The following example command defines a GiST index operator class for the data type _int4
       (array of int4). See the intarray module for the complete example.

           CREATE OPERATOR CLASS gist__int_ops
               DEFAULT FOR TYPE _int4 USING gist AS
                   OPERATOR        3       &&,
                   OPERATOR        6       = (anyarray, anyarray),
                   OPERATOR        7       @>,
                   OPERATOR        8       <@,
                   OPERATOR        20      @@ (_int4, query_int),
                   FUNCTION        1       g_int_consistent (internal, _int4, smallint, oid, internal),
                   FUNCTION        2       g_int_union (internal, internal),
                   FUNCTION        3       g_int_compress (internal),
                   FUNCTION        4       g_int_decompress (internal),
                   FUNCTION        5       g_int_penalty (internal, internal, internal),
                   FUNCTION        6       g_int_picksplit (internal, internal),
                   FUNCTION        7       g_int_same (_int4, _int4, internal);

COMPATIBILITY
       CREATE OPERATOR CLASS is a PostgreSQL extension. There is no CREATE OPERATOR CLASS statement
       in the SQL standard.

SEE ALSO
       ALTER OPERATOR CLASS (ALTER_OPERATOR_CLASS(7)), DROP OPERATOR CLASS (DROP_OPERATOR_CLASS(7)),
       CREATE OPERATOR FAMILY (CREATE_OPERATOR_FAMILY(7)), ALTER OPERATOR FAMILY
       (ALTER_OPERATOR_FAMILY(7))



PostgreSQL 14.23                                2026                        CREATE OPERATOR CLASS(7)