我想检查数据，但如果它为空或空忽略它。目前查询如下…
Select
Coalesce(listing.OfferText, company.OfferText, '') As Offer_Text,
from tbl_directorylisting listing
Inner Join tbl_companymaster company
On listing.company_id= company.company_id
但我想找个伴。OfferText如果列表。Offertext是一个空字符串，如果它是null。
最好的解决方案是什么?
当前回答
防止SQL结果中出现空值或空值的记录
我们可以简单地添加.....WHERE Column_name != "或'null'
其他回答
您可以使用ISNULL并根据已知输出检查答案:
SELECT case when ISNULL(col1, '') = '' then '' else col1 END AS COL1 FROM TEST
这也迎合了空间。
(len(rtrim(ltrim(isnull(MyField,'')))) !=0
COALESCE和NULLIF的简单组合应该可以做到:
SELECT
Coalesce(NULLIF(listing.OfferText, ''), company.OfferText) As Offer_Text
...
注意:如果希望语句返回空字符串而不是NULL(如果两个值都为NULL)，则添加另一个空字符串作为最后一个COALESCE参数。
这里有一个解决方案，但我不知道它是否是最好的....
Select
Coalesce(Case When Len(listing.Offer_Text) = 0 Then Null Else listing.Offer_Text End, company.Offer_Text, '') As Offer_Text,
from tbl_directorylisting listing
Inner Join tbl_companymaster company
On listing.company_id= company.company_id
Select
CASE
WHEN listing.OfferText is null or listing.OfferText = '' THEN company.OfferText
ELSE COALESCE(Company.OfferText, '')
END As Offer_Text,
from tbl_directorylisting listing
Inner Join tbl_companymaster company
On listing.company_id= company.company_id
