Oracle Trigger有条件

Question

我有这个触发器接近我想要完成的但是在尝试之后我仍然无法完成它。

我做了什么

CREATE or REPLACE TRIGGER TR_UPD_TEST_TABLE_B
  AFTER INSERT ON TEST_TABLE_A
  FOR EACH ROW
DECLARE

BEGIN

  FOR VAL IN (SELECT * FROM TEST_TABLE_B A WHERE A.ID = :NEW.ID) LOOP
    IF :NEW.QTY_RECEIVED > VAL.QTY_PRE_RECEIVED THEN
      UPDATE TEST_TABLE_B A SET A.QTY_RECEIVED = 888 WHERE A.ID = :NEW.ID;
    ELSE
      UPDATE TEST_TABLE_B A SET A.QTY_RECEIVED = 111 WHERE A.ID = :NEW.ID;
    END IF;

  END LOOP;

END;

问题

通过使用IF :NEW.QTY_RECEIVED > VAL.QTY_PRE_RECEIVED，我想将：NEW.QTY_RECEIVED与每条记录进行比较，但似乎它总计了所有记录的数量。因此，语句总是跳转到ELSE，因为总数量大于:NEW.QTY_RECEIVED。

Answer 1

你不需要循环。只需使用一个更新和案例即可完成。

CREATE or REPLACE TRIGGER TR_UPD_TEST_TABLE_B
  AFTER INSERT ON TEST_TABLE_A
  FOR EACH ROW
DECLARE

BEGIN
      UPDATE TEST_TABLE_B A SET A.QTY_RECEIVED = 
      case when :NEW.QTY_RECEIVED > QTY_PRE_RECEIVED then 888 else 111 end
      WHERE A.ID = :NEW.ID ;

END;

Answer 2

这是我最终出来的答案。

CREATE or REPLACE TRIGGER TR_UPD_TEST_TABLE_B
  AFTER INSERT ON TEST_TABLE_A
  FOR EACH ROW
DECLARE
  BALQTY NUMBER;
BEGIN
  BALQTY := :NEW.QTY_RECEIVED;
  FOR VAL IN (SELECT A.*
                FROM TEST_TABLE_B A
               WHERE A.ID = :NEW.ID
               ORDER BY A.ID1) LOOP

    IF BALQTY >= VAL.QTY_PRE_RECEIVED THEN
      UPDATE TEST_TABLE_B A
         SET A.QTY_RECEIVED     = A.QTY_RECEIVED + VAL.QTY_PRE_RECEIVED,
             A.QTY_PRE_RECEIVED = 0
       WHERE A.ID1 = VAL.ID1
         AND VAL.QTY_PRE_RECEIVED <> 0;
      BALQTY := BALQTY - VAL.QTY_PRE_RECEIVED;
    ELSIF BALQTY < VAL.QTY_PRE_RECEIVED AND BALQTY <> 0 AND BALQTY > 0 THEN
      UPDATE TEST_TABLE_B A
         SET A.QTY_RECEIVED     = A.QTY_RECEIVED + BALQTY,
             A.QTY_PRE_RECEIVED = VAL.QTY_PRE_RECEIVED - BALQTY
       WHERE A.ID1 = VAL.ID1
         AND VAL.QTY_PRE_RECEIVED <> 0;
      BALQTY := 0;
    ELSIF BALQTY = 0 THEN
      EXIT;
    END IF;

  END LOOP;

END;