SQL 2005中的嵌套选择查询 [英] nested select query in sql 2005

问题描述

我有两个桌子.
1.管理员(用户名，密码)
2.User(用户名，类型)
我已经提供了用户名和密码，我想从User表中检索用户类型.

I have two table.
1.Admin(username,password)
2.User(username,type)
I have given username and password and I want retrieve the type of user from User table.

推荐答案

select type from [User] where username = 'the_username_wanted'

一个简单的连接就是你要的

a simple join is what you are after

SELECT
    *
FROM
    Admin a
JOIN
    User u
ON
    a.username = u.username
WHERE
    a.username = @username
AND
    a.password = @password

关于CP的连接，也有不错的文章此处 [

There is also a good article on CP about joins here[^]

select type from user where username = @username

@username是您必须将其传递给存储过程或sql语句的参数.

@username is a parameter that you have to pass it to stored procedure or sql statement.

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