嵌套子查询是SQL语句中比较常用的一种查询方法，开发过程中遇到查询需要将自己的某列作为待查询的数据，在参考别人的SQL语句的写法终于实现了自己需要的功能。
不太和谐查询语句如下：
SELECT DISTINCT dbo.a.ProxyID, dbo.a.account AS adminAccount, dbo.b.LevelName, dbo.a.ProfitProportion, dbo.a.totalUpScore, dbo.a.score, dbo.a.members, dbo.a.authority, dbo.a.registerDate, dbo.a.freezeState, temp.belongName
FROM dbo.a INNER JOIN dbo.b ON dbo.a.ProxyLevel = dbo.b.LevelId INNER JOIN (SELECT dbo.c.BelongsAgent, a.ProxyID, a.account AS belongName FROM dbo.a AS a INNER JOIN dbo.c ON a.ProxyID = BelongsAgent AND a.ProxyID = dbo.c.BelongsAgent) AS temp ON dbo.a.belongsAgent = temp.BelongsAgent
精简版的查询语句如下：（省略了a表的一些不重要字段）
SELECT DISTINCT dbo.a.BelongAgentId, dbo.a.Account, dbo.b.LevelName, temp.BelongName FROM dbo.a INNER JOIN (SELECT a.Account AS BelongName, a.ProxyId FROM dbo.a AS a INNER JOIN (SELECT BelongAgentId AS id FROM dbo.a AS a) AS t ON a.ProxyId = t.id) AS temp ON dbo.a.BelongAgentId = temp.ProxyId INNER JOIN dbo.b ON dbo.a.ProxyLevel = dbo.b.LevelId
新人报道，希望大家多多帮助，谢谢大家！