navicat 添加 mysql 触发器 多条件if判断 定义变量 先查询后新增

在 navicat 添加触发器

 

 触发器内容

BEGIN 
 DECLARE user_name VARCHAR(20);
 DECLARE user_age INT;
 
 
 IF (NEW.name='张三' && OLD.userAge>18) THEN
	SELECT name, age INTO user_name, user_age FROM extra_info WHERE user_id = NEW.id;
	INSERT into user_form (id,name,age,sex) values (null,user_name,user_age,new.sex)
	else 
	 ...
END IF;

也可以使用 'set'

BEGIN 
 DECLARE user_name VARCHAR(20);
 DECLARE user_age INT;
 

 SET user_name =  new.name;
 
 IF (NEW.name='张三' && OLD.age>18) THEN
	
	INSERT into user_form (id,name,age,sex) values (null,user_name,user_age,new.sex)
	else 
	 ...
END IF;