MySql 未创建触发器。 语法错误：#1064

Question

i have a problem with trigger in MySql. When i create a trigger i have a syntax error

 CREATE TABLE user (
 id int NOT NULL,
 completeName varchar(255) NOT NULL,
 email varchar(255) NOT NULL,
 passw_hash varchar(255) NOT NULL,
 accType varchar(255) NOT NULL,
 PRIMARY KEY (id)
 );
 create or REPLACE trigger test
 AFTER insert on user
 FOR EACH ROW
 BEGIN
 INSERT INTO `user` VALUES (1,'Pinco 
 Pallo','pinco@pallo','zinco','Owner');
 end;

Erorr:#1064

Answer 1

There are 2 errors in shown code.

1. MySQL does not support OR REPLACE in CREATE TRIGGER .

It allows to use CREATE TRIGGER IF NOT EXISTS which forbids the trigger creation if it exists already. If you want to replace trigger then you must drop it then recreate.

https://dev.mysql.com/doc/refman/8.0/en/create-trigger.html https://dev.mysql.com/doc/refman/8.0/en/drop-trigger.html

2. Trigger cannot alter the table which it is defined on.

Trigger will be created. But it will cause Can't update table 'user' in stored function/trigger because it is already used by statement which invoked this stored function/trigger. runtime error.

https://dev.mysql.com/doc/refman/8.0/en/trigger-syntax.html