请教一个sql语句，SQL server中，我怎样查找一个字段为null的数据啊！

[lemontree197977]

SELECT *
FROM mer_info
WHERE (sort_num = NULL)
这样的sql语句什么都查不到啊

[patchclass]

sort_num is NULL

[liuyangxuan]

:)

[faguoshen]

SELECT *
FROM mer_info
WHERE (sort_num IS NULL)

[opolmzy]

is NULL

[cdsun]

sort_num is NULL

[yhd0411]

sort_num is NULL

[AppleBBS]

SELECT *
FROM mer_info
WHERE sort_num is NULL or sort_num=''

[sookeer]

同意楼上

SELECT *
FROM ceshi
WHERE (name IS NULL)
做了个测试 这个样子了

[dbaren]

SELECT *
FROM mer_info
WHERE sort_num is NULL

[wzhiyuan]

SELECT *
FROM mer_info
WHERE (sort_num is NULL)

[MascotDai]

试试这个：select * from mer_info where rs("sort_num")=NULL

[aoenzh]

SELECT *
FROM mer_info
WHERE (sort_num = "")

[haitor88]

select *
from mer_info
where sort_num=''

[chen8967]

这应该是最基本的知识

[泉畔人家]

SELECT *
FROM mer_info
WHERE (sort_num is NULL)

[fenglik]

同意楼上

[yqh1314]

SELECT *
FROM mer_info
WHERE (sort_num is NULL)

[hpj2002]

SELECT *
FROM mer_info
WHERE (sort_num is NULL)

[cnwhitewolf]

SELECT *
FROM mer_info
WHERE sor_num is null

[wen1818]

SELECT * FROM mer_info WHERE sort_num is NULL