例子，實例學習mysql觸發器的用法。

一，準備二張測試表：

1，測試表1

復制代碼 代碼示例:

DROP TABLE IF EXISTS test;

CREATE TABLE test (

id?????????? bigint(11) unsigned NOT NULL AUTO_INCREMENT,

name???????? varchar(100) NOT NULL DEFAULT '',

type???????? varchar(100),

create_time? datetime,

PRIMARY KEY (ID)

) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8;

2，測試表2

復制代碼 代碼示例:

DROP TABLE IF EXISTS test_hisy;

CREATE TABLE test_hisy (

id?????????? bigint(11) unsigned NOT NULL AUTO_INCREMENT,

name???????? varchar(100) NOT NULL DEFAULT '',

type???????? varchar(100),

create_time? datetime,

operation??? varchar(100) COMMENT '操作類型',

PRIMARY KEY (ID)

) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8;

二，mysql觸發器實例

1，insert觸發器

表test新增記錄后，將type值為“1”的記錄同時插入到test_hisy表中(AFTER INSERT：錄入后觸發， BEFORE INSERT：錄入前觸發)

復制代碼 代碼示例:

DELIMITER //

DROP TRIGGER IF EXISTS t_after_insert_test//

CREATE TRIGGER t_after_insert_test

AFTER INSERT ON test

FOR EACH ROW

BEGIN

IF new.type='1' THEN

insert into test_hisy(name, type, create_time, operation)

values(new.name, new.type, new.create_time, 'insert');

END IF;

END;//

2，update觸發器

表test修改時，若type值為“2”則將修改前的記錄同時插入到test_hisy表中(AFTER UPDATE：修改后觸發， BEFORE UPDATE：修改前觸發)

復制代碼 代碼示例:

DELIMITER //

DROP TRIGGER IF EXISTS t_before_update_test//

CREATE TRIGGER t_before_update_test

BEFORE UPDATE ON test

FOR EACH ROW

BEGIN

IF new.type='2' THEN

insert into test_hisy(name, type, create_time, operation)

values(old.name, old.type, old.create_time, 'update');

END IF;

END;//

3，delete觸發器

表test刪除記錄前，將刪除的記錄錄入到表test_hisy中(AFTER DELETE：刪除后觸發， BEFORE DELETE：刪除前觸發)

復制代碼 代碼示例:

DELIMITER //

DROP TRIGGER IF EXISTS t_before_delete_test//

CREATE TRIGGER t_before_delete_test

BEFORE DELETE ON test

FOR EACH ROW

BEGIN

insert into test_hisy(name, type, create_time, operation)

values(old.name, old.type, old.create_time, 'delete');

END;//

備注：以上觸發器例子中出現的new為修改后的數據， old為修改前的數據。