mysql - 使用变量查询.Sql文件

Question

我想像这样执行多个查询

Delete FROM TableA where CreatedBy="2"
Delete FROM TableB where CreatedBy="2"
Delete FROM TableC where CreatedBy="2"
Delete FROM TableD where CreatedBy="2"

我还想使用该 id 进行更多更新和插入查询。甚至 id 也可能会更改。
每次我都必须更改值才能做到这一点。
有什么方法可以声明变量并执行查询例如

var userid=2;
Delete FROM TableA where CreatedBy="userid"
Delete FROM TableB where CreatedBy="userid"
Delete FROM TableC where CreatedBy="userid"
Delete FROM TableD where CreatedBy="userid"

在这里，如果我只更改一个地方，则 id 会随处更改。
我想创建一个 sql 文件并将其运行到我的 MySQL 服务器并更改用户 ID。
有办法做到这一点吗？以及如何？

Answer 1

您可以这样设置 session 变量:

SET @userid := '2';
DELETE FROM `TableA` WHERE `CreatedBy` = @userid;
DELETE FROM `TableB` WHERE `CreatedBy` = @userid;
DELETE FROM `TableC` WHERE `CreatedBy` = @userid;
DELETE FROM `TableD` WHERE `CreatedBy` = @userid;