更新和删除Oracle触发器
问题描述:
几天前发布了一个问题,并成功启动了我的触发器! 但有一些新的问题。更新和删除Oracle触发器
我有两个表:
CREATE TABLE "ASSESSMENT"
( "ASSESSMENT_NAME" VARCHAR2(50) NOT NULL ENABLE,
"DEADLINE_DATE" DATE NOT NULL ENABLE,
CONSTRAINT "ASSESSMENT_PK" PRIMARY KEY ("ASSESSMENT_NAME") ENABLE
)
CREATE TABLE "ASSESSMENT_ANNOUNCEMENT"
( "ASSESSMENT_NAME" VARCHAR2(50) NOT NULL ENABLE,
"DEADLINE_DATE" DATE NOT NULL ENABLE,
"ATTENTION" VARCHAR2(500) NOT NULL ENABLE,
CONSTRAINT "ASSESSMENT_ANNOUNCEMENT_PK" PRIMARY KEY ("ASSESSMENT_NAME") ENABLE
)
触发我:
CREATE OR REPLACE TRIGGER "TEST"
AFTER INSERT OR UPDATE OR DELETE
ON ASSESSMENT
FOR EACH ROW
BEGIN
IF :new.DEADLINE_DATE >= SYSDATE - 7
THEN
INSERT INTO ASSESSMENT_ANNOUNCEMENT(ASSESSMENT_NAME, DEADLINE_DATE ,ATTENTION)
VALUES(:new.ASSESSMENT_NAME, :new.DEADLINE_DATE, 'DEADLINE IS 7 DAYS OR LESS!');
END IF;
END;
插入正常工作跨越表。但是,当我更新ASSESSMENT
表时,插入在ASSESSMENT_ANNOUNCEMENT
表中的新行是 - 它未更新。
从ASSESSMENT
表中删除将从ASSESSMENT
表中删除行,但从 表中删除该行的ASSESSMENT_ANNOUNCEMENT
表。
任何帮助和/或指导将是太棒了!
答
如果要更新或删除ASSESSMENT_ANNOUNCEMENT
中的一行,应该使用update
或delete
声明明确地执行该操作。
使用以下建筑在触发:
IF INSERTING THEN
-- actions for inserting
ELSIF UPDATING THEN
-- actions for updating
ELSE
-- actions for deleting
END IF;
答
只给你一个完整的样本
CREATE OR REPLACE TRIGGER "TEST"
AFTER INSERT OR UPDATE OR DELETE
ON ASSESSMENT
FOR EACH ROW
BEGIN
IF INSERTING THEN
IF :new.DEADLINE_DATE >= SYSDATE - 7
THEN
INSERT INTO ASSESSMENT_ANNOUNCEMENT(ASSESSMENT_NAME, DEADLINE_DATE ,ATTENTION)
VALUES(:new.ASSESSMENT_NAME, :new.DEADLINE_DATE, 'DEADLINE IS 7 DAYS OR LESS!');
END IF;
ELSIF UPDATING THEN
UPDATE ASSESSMENT_ANNOUNCEMENT SET
ASSESSMENT_NAME=:new.ASSESSMENT_NAME,
DEADLINE_DATE=:new.DEADLINE_DATE,
ATTENTION='Deadline Updated'
WHERE ASSESSMENT_NAME=:old.ASSESSMENT_NAME;
ELSE
DELETE ASSESSMENT_ANNOUNCEMENT
WHERE ASSESSMENT_NAME=:old.ASSESSMENT_NAME;
END IF;
END;
根据的PL/SQL代码的真正的业务逻辑和大小,它可能会更清楚创建三个触发器
CREATE OR REPLACE TRIGGER "TEST_AI_TRG" AFTER INSERT ON ASSESSMENT ...
CREATE OR REPLACE TRIGGER "TEST_AU_TRG" AFTER UPDATE ON ASSESSMENT ...
CREATE OR REPLACE TRIGGER "TEST_AD_TRG" AFTER DELETE ON ASSESSMENT ...
另请注意,对于DELETE,NEW.DEADLINE_DATE值将为NULL。 – eaolson 2013-03-02 21:54:04