select CNAME=case when CNAME is null then '4' else '1' end f

来源：学生作业帮编辑：作业帮分类：综合作业时间：2024/07/04 16:52:06

select CNAME=case when CNAME is null then '4' else '1' end from SMPTEL where SMPTEL.Newtel='1585'
select CNAME=case when CNAME is null then '456' else '123' end from SMPTEL where SMPTEL.Newtel='158'
Newtel 没有158 如何让其显示 456
现在什麽都没有

select CNAME=case when CNAME is null then '456' else '123' end from SMPTEL where SMPTEL.Newtel='158'
union all
select '456' where not exists(select 1 from smptel where newtel='158'
如果是oracle就在where前加上from dual,如果是db2就加上from sysibm.sysdummy1

select CNAME=case when CNAME is null then '4' else '1' end f (case A.ZT when 1 then 's318' else null end) CASE a WHEN 1 THEN b ELSE NULL END case when.then.else.end case when then else end c#开发cast( (case when b.pbproject_ID is null then 1 else 0 en SELECT CASE ABC.A WHEN'否' THEN'1' WHEN'是' THEN'-1' END AS 出入 --简单Case函数 CASE sex WHEN '1' THEN '男' WHEN '2' THEN '女' ELSE select Student.Sno,Sname,Ssex,Cname,Grade from Student,SC,Co PLSQL中,select case..when..then..怎么用? WHERE S.Sno=SC.Sno AND Cname!="数据结构"GROUP BY Sname HAVING AV if dw_1.update()=1 then commit; else rollback; end if 是保存按钮的