sql中关于连接查询的问题
组织不清楚，干脆用个例子
给出两个表
员工表Employee，申请表Application，Apl_User和Apl_Checker都是对应表Employee中的Emp_Id，如何用sql语句查询相对应的名字。即最后的结果应该是这样的
[解决办法]
select a.Api_id,e.emp_name,b.emp_name from Apl_User a inner join Employee e
on a.Api_user=e.emp_id
inner join Employee b on a.Api_checker=b.emp_id
[解决办法]
写错了个别名，不好意思
----------------------------------------------------------------
-- Author :DBA_Huangzj(發糞塗牆)
-- Date :2013-11-26 11:12:33
-- Version:
-- Microsoft SQL Server 2012 (SP1) - 11.0.3128.0 (X64)
--Dec 28 2012 20:23:12
--Copyright (c) Microsoft Corporation
--Enterprise Edition (64-bit) on Windows NT 6.2 <X64> (Build 9200: )
--
----------------------------------------------------------------
--> 测试数据：[Employee]
if object_id('[Employee]') is not null drop table [Employee]
go
create table [Employee]([Emp_id] int,[Emp_name] varchar(4))
insert [Employee]
select 1,'张三' union all
select 2,'李四' union all
select 3,'王武'
--> 测试数据：[Application]
if object_id('[Application]') is not null drop table [Application]
go
create table [Application]([apl_id] int,[apl_user] int,[apl_checker] int)
insert [Application]
select 10001,1,3 union all
select 10002,2,3
--------------开始查询--------------------------
select a.apl_id,e.emp_name,c.emp_name
from [Application] a left join Employee e on a.apl_user=e.emp_id
left join employee c on a.apl_checker=c.emp_id
----------------结果----------------------------
/*
(2 row(s) affected)
apl_id emp_name emp_name
----------- -------- --------
10001 张三 王武
10002 李四 王武
*/
