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mysql - 在触发器内使用变量

转载 作者:行者123 更新时间:2023-11-30 01:27:48 26 4
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我正在测试我的触发器,它运行良好,只是我看不出我的变量似乎没有像应有的那样工作。

例如

DELIMITER //
CREATE TRIGGER lestrigger
AFTER INSERT ON examinations
FOR EACH ROW
BEGIN
DECLARE the_last_inserted_id INT ;
DECLARE the_class_id INT;
DECLARE the_year_id INT;

SET the_last_inserted_id = LAST_INSERT_ID();
SET the_class_id = (select examination_class_id from examinations where examination_id = 1);
SET the_year_id = (select examination_class_id from examinations where examination_id = 1);

insert into examination_data (ed_cs_id,ed_examination_id) select cs_id,@the_last_insert_id from class_students where cs_class_id = 1 AND cs_year_id = 1;

END //
DELIMITER ;

在这一行

insert into examination_data (ed_cs_id,ed_examination_id)  select cs_id,the_last_insert_id from class_students where cs_class_id = 1 AND cs_year_id = 1;

the_last_insert_id 被视为一列

当我尝试这个时,@the_last_insert_id,它不被视为一列,但它也不起作用。我还没有尝试其余的变量。

例如,我将如何定义和使用这个 the_last_inserted_id = LAST_INSERT_ID();

最佳答案

可以设置

Select STH into the_last_inserted_id from TBL limit 1;

insert into examination_data (ed_cs_id,ed_examination_id)
select cs_id,the_last_insert_id
from class_students
where cs_class_id = 1 AND cs_year_id = 1;

编辑:@ - 您使用时无需声明,只需设置

Select STH into @new_id from TBL limit 1;

然后

insert into examination_data (ed_cs_id,ed_examination_id)
select cs_id,@the_last_insert_id
from class_students
where cs_class_id = 1 AND cs_year_id = 1;

关于mysql - 在触发器内使用变量,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/17789030/

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