原来的语句正常:
select top 10 topicid,title,boardid,postusername,lastpost,lastposttime,dateandtime from dv_topic where Not Exists(Select dateandtime From dv_topic Where boardid = A.boardid And dateandtime > A.dateandtime) and boardid not in(69,97,107,444,777) order by dateandtime desc
后来欲增加连接查询一个相关联的子段.
dv_board表的BoardName,
连接条件是dv_topic表的boardid等于dv_board表的boardid
select top 10 a.topicid,a.title,a.boardid,a.postusername,a.lastpost,a.lastposttime,a.dateandtime,b.BoardName from dv_topic A Inner join dv_board b on a.boardid=b.boardid
where Not Exists(Select dateandtime From dv_topic Where boardid = A.boardid And dateandtime > A.dateandtime) and boardid not in(69,97,107,444,777) order by dateandtime desc
==
查询出现
Microsoft OLE DB Provider for SQL Server 错误 '80040e14 '
列名 'boardid ' 不明确。
估计是
select top 10 a.topicid,a.title,a.boardid,a.postusername,a.lastpost,a.lastposttime,a.dateandtime,b.BoardName from dv_topic A Inner join dv_board b on a.boardid=b.boardid
where Not Exists(Select dateandtime From dv_topic Where boardid = A.boardid And dateandtime > A.dateandtime) and boardid not in(69,97,107,444,777) order by dateandtime desc
这一段里的后面部分有错误.只运行前部分不会出错.
where Not Exists(Select dateandtime From dv_topic Where boardid = A.boardid
这里应改成什么??
------解决方案--------------------
select top 10 a.topicid,a.title,a.boardid,a.postusername,a.lastpost,a.lastposttime,a.dateandtime,b.BoardName from dv_topic A Inner join dv_board b on a.boardid=b.boardid
where Not Exists(Select dateandtime From dv_topic Where boardid = A.boardid And dateandtime > A.dateandtime) and boardid not in(69,97,107,444,777) order by dateandtime desc
--这个不明确：boardid 包括（A.和B.）
A.boardid not in(69,97,107,444,777) order by dateandtime desc
B.boardid not in(69,97,107,444,777) order by dateandtime desc
------解决方案--------------------
对于两个表中都有的字段名需要指定属于哪个表。
------解决方案--------------------
碰到这种情况直接用：表名.字段 表示
------解决方案--------------------
hehe,发完就解决了
------解决方案--------------------
在前面把 这个字段的所属表名加上就可以了！