SQL Server GROUP BY troubles! - sql

Question

I'm getting a frustrating error in one of my SQL Server 2008 queries. It parses fine, but crashes when I try to execute. The error I get is the following:
Msg 8120, Level 16, State 1, Line 4
Column
'customertraffic_return.company' is
invalid in the select list because it
is not contained in either an
aggregate function or the GROUP BY
clause.
SELECT *
FROM (SELECT ctr.sp_id AS spid,
Substring(ctr.company, 1, 20) AS company,
cci.email_address AS tech_email,
CASE
WHEN rating IS NULL THEN 'unknown'
ELSE rating
END AS rating
FROM customer_contactinfo cci
INNER JOIN customertraffic_return ctr
ON ctr.sp_id = cci.sp_id
WHERE cci.email_address <> ''
AND cci.email_address NOT LIKE '%hotmail%'
AND cci.email_address IS NOT NULL
AND ( region LIKE 'Europe%'
OR region LIKE 'Asia%' )
AND SERVICE IN ( '1', '2' )
AND ( rating IN ( 'Premiere', 'Standard', 'unknown' )
OR rating IS NULL )
AND msgcount >= 5000
GROUP BY ctr.sp_id,
cci.email_address) AS a
WHERE spid NOT IN (SELECT spid
FROM customer_exclude)
GROUP BY spid,
tech_email

Answer 1

Well, the error is pretty clear, no??
You're selecting those columns in your inner SELECT:
spid
company
tech_email
rating
and your grouping only by two of those (GROUP BY ctr.sp_id, cci.email_address).
Either you need group by all four of them (GROUP BY ctr.sp_id, cci.email_address, company, rating), or you need to apply an aggregate function (SUM, AVG, MIN, MAX) to the other two columns (company and rating).
Or maybe using a GROUP BY here is totally the wrong way to do - what is it you're really trying to do here??

Answer 2

The inner query:
SELECT ctr.sp_id AS spid,
Substring(ctr.company, 1, 20) AS company,
cci.email_address AS tech_email,
CASE
WHEN rating IS NULL THEN 'unknown'
ELSE rating
END AS rating
FROM customer_contactinfo cci
INNER JOIN customertraffic_return ctr
ON ctr.sp_id = cci.sp_id
WHERE cci.email_address <> ''
AND cci.email_address NOT LIKE '%hotmail%'
AND cci.email_address IS NOT NULL
AND ( region LIKE 'Europe%'
OR region LIKE 'Asia%' )
AND SERVICE IN ( '1', '2' )
AND ( rating IN ( 'Premiere', 'Standard', 'unknown' )
OR rating IS NULL )
AND msgcount >= 5000
GROUP BY ctr.sp_id,
cci.email_address
has 4 non-aggregate things in the select (sp_id, company, email_address, rating) and you only group on two of them, so it is throwing an error on the first one it sees
So you either need to not group by any of them or group by all of them

Answer 3

i suggest replacing the * with a fully specified column list.

Answer 4

you can either group by all selected columns or use the other columns (not in group by clause) in a aggregate function (like sum)
you cannot: select a,b,c from bla group by a,b
but you can: select a,b,sum(c) from bla groupy by a,b