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drop_operator_class(7) [centos man page]

DROP OPERATOR 
CLASS(7) PostgreSQL 9.2.7 Documentation DROP OPERATOR CLASS(7) NAME
DROP_OPERATOR_CLASS - remove an operator class SYNOPSIS
DROP OPERATOR CLASS [ IF EXISTS ] name USING index_method [ CASCADE | RESTRICT ] DESCRIPTION
DROP OPERATOR CLASS drops an existing operator class. To execute this command you must be the owner of the operator class. DROP OPERATOR CLASS does not drop any of the operators or functions referenced by the class. If there are any indexes depending on the operator class, you will need to specify CASCADE for the drop to complete. PARAMETERS
IF EXISTS Do not throw an error if the operator class does not exist. A notice is issued in this case. name The name (optionally schema-qualified) of an existing operator class. index_method The name of the index access method the operator class is for. CASCADE Automatically drop objects that depend on the operator class. RESTRICT Refuse to drop the operator class if any objects depend on it. This is the default. NOTES
DROP OPERATOR CLASS will not drop the operator family containing the class, even if there is nothing else left in the family (in particular, in the case where the family was implicitly created by CREATE OPERATOR CLASS). An empty operator family is harmless, but for the sake of tidiness you might wish to remove the family with DROP OPERATOR FAMILY; or perhaps better, use DROP OPERATOR FAMILY in the first place. EXAMPLES
Remove the B-tree operator class widget_ops: DROP OPERATOR CLASS widget_ops USING btree; This command will not succeed if there are any existing indexes that use the operator class. Add CASCADE to drop such indexes along with the operator class. COMPATIBILITY
There is no DROP OPERATOR CLASS statement in the SQL standard. SEE ALSO
ALTER OPERATOR CLASS (ALTER_OPERATOR_CLASS(7)), CREATE OPERATOR CLASS (CREATE_OPERATOR_CLASS(7)), DROP OPERATOR FAMILY (DROP_OPERATOR_FAMILY(7)) PostgreSQL 9.2.7 2014-02-17 DROP OPERATOR CLASS(7)

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CREATE OPERATOR 
CLASS(7) SQL Commands 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 ) ] | FUNCTION support_number [ ( op_type [ , op_type ] ) ] funcname ( 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 procedures to be used by the index method when the operator class is selected for an index col- umn. 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 in the documentation 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 left-unary or right-unary operator. The oper- and 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 and hash indexes) or the class's data type (for GIN and GiST indexes). These defaults are always correct, so there is no point in specifying op_type in a FUNCTION clause in CREATE OPERATOR CLASS, but the option is provided for consistency with the comparable syntax in ALTER OPERATOR FAMILY. support_number The index method's support procedure number for a function associated with the operator class. funcname The name (optionally schema-qualified) of a function that is an index method support procedure for the operator class. argument_types 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 GIN and GiST) allow it to be different. The STORAGE clause must be omitted unless the index method allows a different type to be used. 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 opera- tor class is tantamount to granting public execute permission on it. This is usually not an issue for the sorts of functions that are use- ful in an operator class. 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 defines a GiST index operator class for the data type _int4 (array of int4). See contrib/intarray/ 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, int, 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_fam- ily(7)], ALTER OPERATOR FAMILY [alter_operator_family(7)] SQL - Language Statements 2010-05-14 CREATE OPERATOR CLASS(7)
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