sqlserver3,sqlserver3417错误

关于.asp中的sqlserver3张表的多表查询

具体要查哪个字段，你自己修改吧，我帮你把表之间的链接条件写出来。

select a.*, b.*, c.* from a, b, c where a.a1 = b.b1 and a.a2 = c.c2 and a2 = an

相关问答

Q1: 无法启动sql server(mssqlserver)服务 错误3:系统找不到指定的路径

解决方案

既然知道了问题所在，那么久好解决了。找到SQL SERVER安装路径，Binn目录下，找到这个文件：

右键用超级管理员账户运行，就可以发现Sql server提供服务了！

sqlserverstart

虽然运行成功了，但是总不能每次去运行吧。所以我再写一段批处理，保存为bat文件运行即可。批处理内容：

@echo off

SC CREATE mssqlserver binPath= "D:\Program Files\Microsoft SQL Server\MSSQL10.MSSQLSERVER\MSSQL\Binn\sqlservr.exe" DisplayName= "SQL Server" start= auto

REG ADD HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\mssqlserver /v Description /t REG_SZ /d "用于提供SQL SERVER服务的服务，如果停止，则无法提供SQL SERVER服务。"

NET START mssqlserver

注意：以上代码中路径部分，请修改为本机Sqlserver安装路径。

Q2: sqlserver三表联查sql语句

假设学生表叫student,课程表叫class,选课表叫choose

1.三层嵌套的问题

select student.name from student where student.id IN

(select choose.sid from choose where choose.cid NOT IN

(select class.id from class where class.teacher='李明'))

2.一个内连接，一个嵌套

select student.name,avg(choose.score) from

student inner join choose on student.id=choose.sid

where student.id IN

(select choose.sid from choose

where choose.score'60'

group by choose.sid

having count(choose.sid)=2)

gruop by student.id

3.一个联合查询，一个嵌套查询

select student.name from student

where student.id IN

(select c1.sid from choose c1 where choose.cid='1'

union

select c2.sid from choose c2 where choose.cid='2'

on c1.sid=c2.sid

)

4.其实就是自连接查询和行列交换的问题：

select student.id,

(case choose.id when '1' then choose.score end) as 1号课成绩,

(case choose.id when '2' then choose.score end) as 2号课成绩,

from student inner join choose on student.id=choose.sid sc1,

student inner join choose on student.id=choose.sid sc2

where sc1.id='1'

and sc2.id='2'

and sc1.scoresc2.score