Question

我想使用select查询的结果作为另一个select查询的输入值。

以下是一个例子：

SET @name = 'Tony';
select * from People where name=@name;

返回包含2列的表姓氏

Tony Danza
Tony Bennett

然后，我想使用第一条记录的姓氏来查找订阅。

select * from Subscription where user='Danza';

是否可以使用占位符/公式而不是键入“Danza＆＃39;手动？类似的东西：

select * from Subscription where user=(result from first query);

我有8个选择查询，这些查询取决于先前选择查询的结果，因此我不确定是否可以使用联接。即名称＆gt;姓氏＆gt;订阅＆gt; readerID＆gt; deviceId＆gt;等

我试图找到记录然后删除它们。以下是我尝试使用的实际查询

SET @readerId=-7256784839031027017; // set manually
select * from Reader where readerId=@readerId;

SET @readersId=788216; // use the previous query's readerId column
select * from Reader_Device where READERS_ID=@readersId;

SET @deviceId=786527; // use the previous query's DEVICES_ID column
select * from Device where id=@deviceId;

SET @subscriptionValue='B1AA9B9FFBAE46918C079CAEC06EDC3B'; // use the previous query's deviceId column
select * from Subscription_attributes where KEY0='deviceId' and value=@subscriptionValue;

SET @subscriptionId=786618; // use the previous query's SUBSCRIPTION_ID column

delete from Installation where DEVICE_REF=@deviceId;
delete from Reader_Device where DEVICES_ID=@deviceId;
delete from Device where id=@deviceId;
delete from Subscription_attributes where KEY0='deviceId' and value=@subscriptionValue;
delete from Subscription_attributes where SUBSCRIPTION_ID=@subscriptionId;
delete from Subscription where id=@subscriptionId;
delete from Reader where readerId=@readerId;

Answer 1

加入：

select s.* from subscription s join people p on s.user = p.surname
where p.name = @name  /* modify as per your requirement */

by in clause：

select * from subscription
where user in(select surname from people where name = @name)

我希望这会有所帮助。

如何使用查询结果作为另一个查询的输入？

1 个答案: