DROP OPERATOR CLASS - 刪除一個操作符類
SYNOPSISDROP OPERATOR CLASS name USING index_method [ CASCADE | RESTRICT ]
DESCRIPTION 描述DROP OPERATOR CLASS 從資料庫中刪除一個現有操作符表。要執行這條命令,你必須是此操作符表的所有者。
PARAMETERS 參數name一個現存操作符表的名字(可以用模式修飾)。 index_method
操作符表所對付的索引訪問方法的名字。 CASCADE
自動刪除依賴於該操作符表的對象。 RESTRICT
如果有任何依賴對象存在,則拒絕刪除此操作符表。這個行為是預設。 EXAMPLES 例子
刪除 B-tree 操作符表 widget_ops:
DROP OPERATOR CLASS widget_ops USING btree;
如果有任何現存的索引使用這個操作符表,那麼這條命令將不能 執行。增加一個 CASCADE 刪除這樣的索引以及這個 操作符表。
在 SQL 標準裡沒有 DROP OPERATOR CLASS。
ALTER OPERATOR CLASS [alter_operator_class(7)], CREATE OPERATOR CLASS [create_operator_class(l)]
NAMEDROP OPERATOR CLASS - remove an operator class
SYNOPSISDROP OPERATOR CLASS name USING index_method [ CASCADE | RESTRICT ]
DESCRIPTIONDROP OPERATOR CLASS drops an existing operator class. To execute this command you must be the owner of the operator class.
PARAMETERSname 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. EXAMPLESRemove 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.
COMPATIBILITYThere is no DROP OPERATOR CLASS statement in the SQL standard.
SEE ALSOALTER OPERATOR CLASS [alter_operator_class(7)], CREATE OPERATOR CLASS [create_operator_class(l)]
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