SQL判断 一个字段为空时，取出另一个字段数据。判断怎么写？？？？？？

[nick_nie]

其中一个字段为空时，取出另一个字段数据。

例：NewsShortTitle不为空取出，为空标题取出NewsTitle

SELECT TOP 5
NewsID,ClassID,
(select ClassName from CMS_ClassNode where ClassID=View_News.ClassID)
as ClassName,NewsTitle,NewsShortTitle,
NewsAuthor,NewsUrlFrom,NewsPic,
NewsCss,NewsDes,NewsHit,NewsTJ,
NewsCheck,NewsIsToHtml,AddTime,ModTime,ModAdminName
from View_News where ClassID IN('13') order by AddTime DESC

[emeng0806]

[Quote=引用 3 楼 hao1hao2hao3 的回复:]
就是isnull函数--isnull(NewsShortTitle,NewsTitle)
[/Quote]

up~

[yigerendeC]

isnull up~

[baiying15]

[Quote=引用 3 楼 hao1hao2hao3 的回复:]
就是isnull函数--isnull(NewsShortTitle,NewsTitle)
[/Quote]

顶。。

[ask_chang]

COALESCE
取第一个非空值

[xulehome]

isnull

[huangdh12]

case when end

[duanzhi1984]

case when then end

isnull

COALESCE

[dawugui]

select case when NewsShortTitle is not null then NewsShortTitle else NewsTitle end from tb

[hao1hao2hao3]

用

SELECT TOP 5
NewsID,ClassID,
(select ClassName from CMS_ClassNode where ClassID=View_News.ClassID)  
as ClassName,NewsTitle,isnull(NewsShortTitle,NewsTitle) as NewsShortTitle,
NewsAuthor,NewsUrlFrom,NewsPic,
NewsCss,NewsDes,NewsHit,NewsTJ,
NewsCheck,NewsIsToHtml,AddTime,ModTime,ModAdminName  
from View_News where ClassID IN('13') order by AddTime DESC

[hao1hao2hao3]

就是isnull函数--isnull(NewsShortTitle,NewsTitle)

[TheGodOfGods]

COALESCE函数--COALESCE(NewsShortTitle,NewsTitle)

[喜-喜]

[Quote=引用 3 楼 hao1hao2hao3 的回复:]
就是isnull函数--isnull(NewsShortTitle,NewsTitle)
[/Quote]

up..

[liyingjie5360]

[Quote=引用 12 楼 duanzhi1984 的回复:]
case when then end

isnull

COALESCE
[/Quote]

都行

[幸运的意外]

用isnull函数吧，这个判断两个字段最好了。