不工作的组 - 非常基础

Question

i did a few searches and i saw a few people try to do some kind of nested select statement in order to fix the issue. i did not understand it.

can someone help me please:

the data is already sorted by provider name, each provider name is listed more than once based on various other columns in the table. however, when i do this, i do not get one line per provider name. instead the provider names repeat as if i am not using group by

here is the code:

create table moopnjsummary2 as

select mnj.ProviderName
from moopnj mnj
group by mnj.ProviderName

Answer 1

Do you want a list of mnj.ProviderName without repeats? What is your final goal?

You could also try SELECT DISTINCT

Answer 2

select mnj.ProviderName, count(*) as Providernamecount
from moopnj mnj 
group by mnj.ProviderName 

Answer 3

如果您要查找的是不同的ProviderNames，请尝试运行

SELECT DISTINCT moopnj.ProviderName FROM moopnj

Answer 4

This is a not a full answer to your question but if all you want is a list of provider names you should use: "Select DISTINCT mnj.ProviderName ...". That will eliminiate all duplicates.