RACLE将等待，直到数据行解锁。
在UPDATE和DELETE中使用WHERE CURRENT OF子串的语法如下：
| WHERE{CURRENT OF cursor_name|search_condition} |
例：
| DELCARE
CURSOR c1 IS SELECT empno,salary
FROM emp
WHERE comm IS NULL
FOR UPDATE OF comm;
v_comm NUMBER(10,2);
BEGIN
FOR r1 IN c1 LOOP
IF r1.salary<500 THEN
v_comm:=r1.salary*0.25;
ELSEIF r1.salary<1000 THEN
v_comm:=r1.salary*0.20;
ELSEIF r1.salary<3000 THEN
v_comm:=r1.salary*0.15;
ELSE
v_comm:=r1.salary*0.12;
END IF;
UPDATE emp
SET comm=v_comm
WHERE CURRENT OF c1;
END LOOP;
END |
|