JOIN tables inside a subquery in DB2 - db2

Question

I'm having trouble with paginating with joined tables in DB2. I want to return rows 10-30 of a query that contains an INNER JOIN.
This works:
SELECT *
FROM (
SELECT row_number() OVER (ORDER BY U4SLSMN.SLNAME) AS ID,
U4SLSMN.SLNO, U4SLSMN.SLNAME, U4SLSMN.SLLC
FROM U4SLSMN) AS P
WHERE P.ID BETWEEN 10 AND 30
This does not work:
SELECT *
FROM (
SELECT row_number() OVER (ORDER BY U4SLSMN.SLNAME) AS ID,
U4SLSMN.SLNO, U4SLSMN.SLNAME, U4SLSMN.SLLC, U4CONST.C4NAME
FROM U4SLSMN INNER JOIN U4CONST ON U4SLSMN.SLNO = U4CONST.C4NAME
) AS P
WHERE P.ID BETWEEN 10 AND 30
The error I get is:
Selection error involving field *N.
Note that the JOIN query works correctly by itself, just not when it's run as a subquery.
How do I perform a join inside a subquery in DB2?

Answer 1

Works fine for me on v7.1 TR9
Here's what I actually ran:
select *
from ( select rownumber() over (order by vvname) as ID, idescr, vvname
from olsdta.ioritemmst
inner join olsdta.vorvendmst on ivndno = vvndno
) as P
where p.id between 10 and 30;
I much prefer the CTE version however:
with p as
( select rownumber() over (order by vvname) as ID, idescr, vvname
from olsdta.ioritemmst
inner join olsdta.vorvendmst on ivndno = vvndno
)
select *
from p
where p.id between 10 and 30;
Finally, note that at 7.1 TR11 (7.2 TR3), IBM added support of the LIMIT and OFFSET clauses. Your query could be re-done as follows:
SELECT
U4SLSMN.SLNO, U4SLSMN.SLNAME, U4SLSMN.SLLC, U4CONST.C4NAME
FROM U4SLSMN INNER JOIN U4CONST ON U4SLSMN.SLNO = U4CONST.C4NAME
ORDER BY U4SLSMN.SLNAME
LIMIT 20 OFFSET 9;
However, note that the LIMIT & OFFSET clauses are only supported in prepared or embedded SQL. You can't use them in STRSQL or STRQMQRY. I believe the "Run SQL Scripts" GUI interface does support them. Here's an article about LIMIT & OFFSET