WHERE CURRENT OF

如果你想删除或者更新被Select For Update引用的记录，你可以使用Where Current Of语句。

UPDATE table_nameSET set_clauseWHERE CURRENT OF cursor_name;
OR
DELETE FROM table_name
WHERE CURRENT OF cursor_name;

Where Current Of语句允许你更新或者是删除最后由cursor取的记录。

下面一个使用Where Current Of更新记录的例子：

CREATE OR REPLACE Function FindCourse( name_in IN varchar2 )RETURN number
IScnumber number;CURSOR c1ISSELECT course_number, instructorfrom courses_tblwhere course_name = name_inFOR UPDATE of instructor;BEGIN
open c1;
fetch c1 into cnumber;if c1%notfound thencnumber := 9999;
elseUPDATE courses_tblSET instructor = 'SMITH'WHERE CURRENT OF c1;COMMIT;
end if;close c1;
RETURN cnumber;
END;

Deleting using the WHERE CURRENT OF Statement
Here is an example where we are deleting records using the Where Current Of Statement:
译：下面一个使用Where Current Of删除记录的例子：

CREATE OR REPLACE Function FindCourse( name_in IN varchar2 )RETURN number
IScnumber number;CURSOR c1ISSELECT course_number, instructorfrom courses_tblwhere course_name = name_inFOR UPDATE of instructor;BEGIN
open c1;
fetch c1 into cnumber;if c1%notfound thencnumber := 9999;
elseDELETE FROM courses_tblWHERE CURRENT OF c1;COMMIT;
end if;close c1;
RETURN cnumber;
END;

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WHERE CURRENT OF

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