Question

RDBMS SQL Server, T-SQL

Consider a table that links information from two different tables: Articles and Categories. This table contains for each Article one or several entries containing the ID of the Categories the Article belongs to. Therefore, a

SELECT * FROM TABLE WHERE ARTICLEID = X 

returns 1 to n results.

I am looking to build a query which allows me to compare Articles that have the exact same combination of Categories. I’ve been trying with INTERSECT, but that does not return any rows. An example:

ARTICLEID  CATEGORYID

    1  1
    1  2
    1  4
    2  1
    2  4
    3  1
    3  2
    3  4
    4  2
    4  4
    5  1
    5  2
    5  4

The query for ARTICLEID = 1 should return 3 and 5, for ARTICLEID = 3 should return 1 and 5, et cetera.

Answer 1

EDITed: This should work

with temp as
(
    select a.*, b.articleid as bart, 1 as cnt from tableName a left join
    tableName b on a.CATEGORYID=b.CATEGORYID where a.articleid=XXX
)
select bart from temp where bart<>articleid group by bart having sum(cnt) =
(select count(*) from tableName where articleid=XXX)

Just run this exact query, changing only the XXX to whatever articleID that you need to match. It should work.