如果数据库中有很多Email 地址
比如
adfafd@yahoo.ac
adfasdfa@yahoo.nz
adfadf@yahoo.cn
请问如何选择只要那个email provider, 并且计数。
对于上面那种情况的话
最后结果应该是
Email_Provider Number
yahoo 3
------解决思路----------------------
-- drop table #temp
create table #temp(Email_Provider varchar(50))
insert into #temp(Email_Provider)
values('adfafd@yahoo.ac'),('adfasdfa@yahoo.nz'),('adfadf@yahoo.cn'),(null)
select * from #temp
;with tab as(
select LEFT(STUFF(Email_Provider,1,CHARINDEX('@',Email_Provider),''),CHARINDEX('.',STUFF(Email_Provider,1,CHARINDEX('@',Email_Provider),''))-1) as Email_Provider
from #temp)
select Email_Provider,COUNT(*)
from tab
group by Email_Provider