NAME

DROP OPERATOR - 刪除一個(gè)操作符

SYNOPSIS

DROP OPERATOR name ( lefttype | NONE , righttype | NONE ) [ CASCADE | RESTRICT ]

DESCRIPTION 描述

DROP OPERATOR 語句從數(shù)據(jù)庫中刪除一個(gè)現(xiàn)存的操作符。 要執(zhí)行這個(gè)命令，你必須是操作符所有者。  

PARAMETERS 參數(shù)

name

 一個(gè)現(xiàn)存的操作符的名字（可以有模式修飾）。

lefttype

 該操作符左參數(shù)的類型。如果該操作符沒有左參數(shù)， 寫 NONE。

righttype

 該操作符右參數(shù)的類型。如果該操作符沒有右參數(shù)， 寫 NONE。

CASCADE

 自動(dòng)刪除依賴于此操作符的對(duì)象。

RESTRICT

 如果有任何依賴對(duì)象則拒絕刪除此操作符。這個(gè)是缺省。

EXAMPLES 例子

 將用于integer的冪操作符 a^n 刪除：

DROP OPERATOR ^ (integer, integer);

 為類型 bit 刪除左單目位操作符 ~b： ~b for type bit:

DROP OPERATOR ~ (none, bit);

 刪除用于 integer 的階乘 （x!） ：

DROP OPERATOR ! (integer, none);

COMPATIBILITY 兼容性

 在 SQL 標(biāo)準(zhǔn)里沒有 DROP OPERATOR 語句。  

SEE ALSO 參見

CREATE OPERATOR [create_operator(7)]

#p#

NAME

DROP OPERATOR - remove an operator

SYNOPSIS

DROP OPERATOR name ( lefttype | NONE , righttype | NONE ) [ CASCADE | RESTRICT ]

DESCRIPTION

DROP OPERATOR drops an existing operator from the database system. To execute this command you must be the owner of the operator.  

PARAMETERS

name

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

lefttype

The data type of the operator's left operand; write NONE if the operator has no left operand.

righttype

The data type of the operator's right operand; write NONE if the operator has no right operand.

CASCADE

Automatically drop objects that depend on the operator.

RESTRICT

Refuse to drop the operator if any objects depend on it. This is the default.

EXAMPLES

Remove the power operator a^b for type integer:

DROP OPERATOR ^ (integer, integer);

Remove the left unary bitwise complement operator ~b for type bit:

DROP OPERATOR ~ (none, bit);

Remove the right unary factorial operator x! for type integer:

DROP OPERATOR ! (integer, none);

COMPATIBILITY

There is no DROP OPERATOR statement in the SQL standard.  

SEE ALSO

CREATE OPERATOR [create_operator(7)]