SQL Comma Separated List from Multiple Columns - sql

Question

I have data that looks like this:
CUSTOMER_ID OPERDAYSJUL OPERDAYSAUG OPERDAYSSEP ... OPERDAYSJUN
1 30 15 2
2 5 1 0
3 6 0 12
4 12 5 23
For each customer_id, I want a comma-delimited list indicating which months the customer operates:
CUSTOMER_ID OPERATING_MONTHS
1 Jul, Aug, Sep
2 Jul, Aug
3 Jul, Sep
4 Jul, Aug, Sep
and so forth. How might I use SQL Server 2005 SQL (not T-SQL) to easily produce this comma-delimited list?
Most solutions I see here on Stack Overflow and elsewhere seem to create comma-separated lists based on joining multiple rows values, not column values:
T-SQL
FOR XML PATH('')
Correlated subquery combined with REPLACE/STUFF/SUBSTRING
Am I missing something obvious? Thanks in advance for assistance or pointer to appropriate existing solution here.

Answer 1

This strips off the extra comma
SELECT
CUSTOMER_ID,
SUBSTRING(
CASE WHEN OPERDAYSJUL > 0 THEN ', Jul' ELSE '' END +
CASE WHEN OPERDAYSAUG > 0 THEN ', Aug' ELSE '' END +
...
CASE WHEN OPERDAYSJUN > 0 THEN ', Jun' ELSE '' END,
3, 255)
FROM TheTable

Answer 2

declare #t table (CUSTOMER_ID int
, OPERDAYSJUL int
, OPERDAYSAUG int
, OPERDAYSSEP int
-- ... rest of 9 months here
);
insert into #t (CUSTOMER_ID, OPERDAYSJUL, OPERDAYSAUG, OPERDAYSSEP)
select 1, 30, 15, 22 union all
select 2, 0, 10, 10 union all
select 3, 0, 0, 10 union all
select 4, 0, 0, 0 union all
select 5, 10, 0, 10 union all
select 6, 10, 10, 0 union all
select 7, 0, 10, 0 union all
select 8, 10, 0, 0;
with cte_months as (
select CUSTOMER_ID
, case when OPERDAYSJUL=0 then '' else ', Jul' end
+ case when OPERDAYSAUG=0 then '' else ', Aug' end
+ case when OPERDAYSSEP=0 then '' else ', Sep' end
-- ... rest of 9 months here
as month_list
from #t)
select CUSTOMER_ID, substring(month_list, 3, 70)
from cte_months;

Answer 3

You can do something like this.
CONCAT(CASE OPERDAYSJUL > 0 THEN "Jul," ELSE "" END,CASE OPERDAYSAUG > 0 THEN "Aug" ELSE "" END ... )

Answer 4

Assuming your table has 13 columns (1 for each month of the year + CUSTOMER_ID), you can write something like:
SELECT
CUSTOMER_ID,
CASE OPERDAYSJUL > 0 THEN 'Jul,' ELSE '' END +
CASE OPERDAYSAUG > 0 THEN 'Aug,' ELSE '' END +
...
FROM MyTable
and build up a string that represents your comma-separated list using CASE statements, one for each month.

Answer 5

select
customer_id,
case when len(operating_month) > 0 then
left(operating_month, len(operating_month) - 1)
else
operating_month
end as operating_month
from
(
SELECT CUSTOMER_ID,
CASE OPERDAYSJUL > 0 THEN 'Jul,' ELSE '' END
+ CASE OPERDAYSAUG > 0 THEN 'Aug,' ELSE '' END
+ ...
as operating_month
FROM MyTable
) as x