SQLite After Delete
它指定在删除数据后如何创建触发器。我们有两个表COMPANY和AUDIT。
COMPANY表:
CREATE TABLE COMPANY(
ID int PRIMARY KEY NOT null,
NAME TEXT NOT null,
AGE int NOT null,
ADDRESS CHAR(50),
SALARY REAL
);
审核表:
CREATE TABLE AUDIT(
EMP_ID int NOT null,
ENTRY_DATE TEXT NOT null
);
删除后创建触发器:
使用以下语法在删除操作后在COMPANY表上创建名为" after_del"的触发器。
CREATE TRIGGER after_del AFTER DELETE
ON COMPANY
BEGIN
INSERT INTO AUDIT(EMP_ID, ENTRY_DATE) VALUES (new.ID, datetime('now'));
END;
现在从旧表中删除记录:
请参见触发器:
SELECT name FROM sqlite_master
WHERE type = 'trigger';
输出: