mysql触发器语法及实例

mysql触发器：

1.语法： create trigger trigger_name trigger_time trigger_event on table_name for each row trigger_stmt

trigger_time:是触发动作时间，可以是before或者after trigger_event:是触发语句类型，可以是insert ,update,delete trigger_stmt:是触发之后需要做什么，如果是多个语句需要用begin end

2.实例

示例一  
    delimiter //    
    create trigger InsertUser    
    before insert on user   
    for each row    
    Begin   
    insert into user_group(uid,gid) values(new.uid,group4444444444);    
    end;//    
    delimiter ;

示例二    
    delimiter //    
    create trigger InsertUser    
    before insert on user   
    for each row    
    Begin   
    IF new.Type=2 then   
    insert into user_group(uid,gid) values(new.uid,group4444444444);    
    else   
    insert into user_group(uid,gid) values(new.uid,group55555555555)    
    END IF;    
    end;//    
    delimiter ;

示例三：    
    delimiter //    
    create trigger InsertUser    
    before insert on user   
    for each row    
    Begin   
    IF new.type=1 then   
    insert into user_group(uid,gid) values(new.uid,578d3369633b47bd9c1fe8bf905cbfb1);    
    END IF;    
    IF new.type=2 then   
     insert into user_group(uid,gid) values(new.uid,387bcd57fc5a4c3c9de83ee210fef661);    
    END IF;    
    end;//    
    delimiter ;