Question

我正在尝试在mysql中设置触发器。实际上我正在尝试将最后插入的记录从notes表插入到log_trigger中，但是下面的代码不能正常工作。

DELIMITER $$
CREATE TRIGGER `after_note` 
    AFTER INSERT ON `notes`
    FOR EACH ROW 
    BEGIN
    INSERT INTO log_trigger (NoteId, customerContact, customer, users, note, NoteCreatedTs) 
    SELECT Id, customerContact, customer, users, note, CreatedBy FROM notes ORDER BY id DESC LIMIT 1
    END$$
DELIMITER ;

请建议

Answer 1

您无需使用select从使用触发器的同一表中选择最后一个数据。您可以使用new关键字。

delimiter //

create trigger after_note after insert on notes
for each row 
begin
insert into log_trigger 
(NoteId, customerContact, customer, users, note, NoteCreatedTs)
values
(new.id,new.customerContact,new.customer,new.users,new.note,new.CreatedBy);
end;//

delimiter ;

Answer 2

不是引用实际notes表中的物理行，而是引用New伪行（它将匹配被触发的基础表的列定义）：

INSERT INTO log_trigger (NoteId, customerContact, customer, users, note, NoteCreatedTs)   
SELECT New.PostId, New.customerContact, New.customer, New.users, New.note, New.CreatedBy;

New已经包含新插入的行 - 您不需要再次找到它。

SqlFiddle here

插入触发器后无法在Mysql中工作

2 个答案: