Mysql trigger instance

Test Table 1

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;  

Test Table 2

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 'Operation type', primary key (ID) ENGINE = InnoDB AUTO_INCREMENT = 1 default charset = utf8;

Insert trigger

AFTER adding a record to table test, INSERT the record with the type Value of "1" to the table test_hisy at the same time (after insert: triggered AFTER input, before insert: triggered BEFORE input)

DELIMITER //DROP TRIGGER IF EXISTS t_after_insert_test//CREATE TRIGGER t_after_insert_testAFTER INSERT ON testFOR EACH ROWBEGIN    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;//

Update trigger

When the table test is modified, if the type value is "2", the records BEFORE modification are inserted to the test_hisy table at the same time (after update: triggered AFTER modification, before update: triggered BEFORE modification)

DELIMITER //DROP TRIGGER IF EXISTS t_before_update_test//CREATE TRIGGER t_before_update_testBEFORE UPDATE ON testFOR EACH ROWBEGIN    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;//

Delete trigger

BEFORE the table test deletes a record, the deleted record is input to the table test_hisy (triggered after delete: triggered AFTER deletion, before delete: triggered BEFORE deletion)

DELIMITER //DROP TRIGGER IF EXISTS t_before_delete_test//CREATE TRIGGER t_before_delete_testBEFORE DELETE ON testFOR EACH ROWBEGIN    insert into test_hisy(name, type, create_time, operation)     values(old.name, old.type, old.create_time, 'delete');END;//

Note: In the above trigger example, the new is the modified data, and the old is the data before the modification.