SQL Server : Group By causes "column invalid" error, how to solve that? - sql

Question

I am trying to filter cg_group names (please check the query) and group (using: GROUP BY) the results according to last updated opportunity (using: ORDER BY opportunities.date_modified DESC).
When I used query without use group by it returns the following results:
SELECT cg_groups.name
FROM cg_groups
JOIN cg_groups_cstm ON cg_groups_cstm.id_c = cg_groups.id
JOIN accounts_cstm ON cg_groups.name = accounts_cstm.client_group_c
JOIN accounts ON accounts.id = accounts_cstm.id_c
JOIN accounts_opportunities ON accounts.id = accounts_opportunities.account_id
JOIN opportunities ON accounts_opportunities.opportunity_id = opportunities.id
WHERE cg_groups.deleted='0' AND cg_groups_cstm.status_c='1' AND opportunities.deleted='0'
ORDER BY opportunities.date_modified DESC
Results:
ABC Group
ABC Group
CBC Group
ABC Group
XYZ Group
But I want to group this to following order:
ABC Group
CBC Group
XYZ Group
To do that I added GROUP BY cg_groups.name
SELECT cg_groups.name
FROM cg_groups
JOIN cg_groups_cstm ON cg_groups_cstm.id_c = cg_groups.id
JOIN accounts_cstm ON cg_groups.name = accounts_cstm.client_group_c
JOIN accounts ON accounts.id = accounts_cstm.id_c
JOIN accounts_opportunities ON accounts.id = accounts_opportunities.account_id
JOIN opportunities ON accounts_opportunities.opportunity_id = opportunities.id
WHERE cg_groups.deleted='0' AND cg_groups_cstm.status_c='1' AND opportunities.deleted='0'
GROUP BY cg_groups.name
ORDER BY opportunities.date_modified DESC
But now I get this error:
Msg 8127, Level 16, State 1, Line 10
Column "opportunities.date_modified" is invalid in the ORDER BY clause because it is not contained in either an aggregate function or the GROUP BY clause.
Someone please help me to solve this issue, thank you.

Answer 1

Use ROW_NUMBER to find the most recently updated record for each group:
WITH cte AS (
SELECT cg_groups.name, o.date_modified,
ROW_NUMBER() OVER (PARTITION BY o.date_modified DESC) rn
FROM cg_groups cg
INNER JOIN cg_groups_cstm cgc
ON cgc.id_c = cg.id
INNER JOIN accounts_cstm ac
ON cg.name = ac.client_group_c
INNER JOIN accounts a
ON a.id = ac.id_c
INNER JOIN accounts_opportunities ao
ON a.id = ao.account_id
INNER JOIN opportunities o
ON ao.opportunity_id = o.id
WHERE cg.deleted = '0' AND cgc.status_c = '1' AND o.deleted = '0'
)
SELECT name
FROM cte
WHERE rn = 1
ORDER BY date_modified DESC;
Note that this may not be exactly what you want. This answer returns a single record per name group which is the most recently updated for that group. It then orders all results descending, but maybe you want ascending.

Answer 2

put opportunities.date_modified in selection and group by then you can use that in order by
SELECT opportunities.date_modified,cg_groups.name
FROM cg_groups
JOIN cg_groups_cstm ON cg_groups_cstm.id_c = cg_groups.id
JOIN accounts_cstm ON cg_groups.name = accounts_cstm.client_group_c
JOIN accounts ON accounts.id = accounts_cstm.id_c
JOIN accounts_opportunities ON accounts.id = accounts_opportunities.account_id
JOIN opportunities ON accounts_opportunities.opportunity_id = opportunities.id
WHERE cg_groups.deleted='0' AND cg_groups_cstm.status_c='1' AND opportunities.deleted='0'
GROUP BY cg_groups.name,opportunities.date_modified
ORDER BY opportunities.date_modified DESC
but for your result you can try like below just use distinct
SELECT distinct cg_groups.name
FROM cg_groups
JOIN cg_groups_cstm ON cg_groups_cstm.id_c = cg_groups.id
JOIN accounts_cstm ON cg_groups.name = accounts_cstm.client_group_c
JOIN accounts ON accounts.id = accounts_cstm.id_c
JOIN accounts_opportunities ON accounts.id = accounts_opportunities.account_id
JOIN opportunities ON accounts_opportunities.opportunity_id = opportunities.id
WHERE cg_groups.deleted='0' AND cg_groups_cstm.status_c='1' AND opportunities.deleted='0'
order by cg_groups.name
no group by need as you have not used any aggregate function

Answer 3

how about just adding distinct right after your SELECT statement .
Select distinct ... from ...