Question

I am wrangling with a query pulling unique values from 3 tables. Is this better done in 2 separate queries?

the query is to:

count as returned (
all leadID from lds where status = "ok"
AND leadID is also in rlds with recID="999"
AND rdate > (03-20-2012)
 + 
(all distinct leadID from plds where recID="999"
AND change != NULL
AND pdate > (03-20-2012)) 

the result of the working query should be “2”: leadID 1 and leadID 4

table lds:

leadID | status
1 | ok
2 | bad
3 | ok

table plds:
leadID | recID | change | pdate
4 | 999 | ch1 | 03-27-2012
4 | 999 | ch2 | 03-27-2012
5 | 888 | NULL | 03-27-2012

table rlds:
leadID | recID2 | rdate
1 | 999 | 03-27-2012
6 | 999 | 03-27-2012

Thanks!

Answer 1

SELECT Ids.leadId
FROM
    Ids JOIN
    rlds ON rlds.leadId = Ids.LeadId AND recID = 999 AND rdate > '03-20-2012'
WHERE Ids.Status = 'ok'

UNION

SELECT leadId
FROM pIds
WHERE recID = 999 AND change IS NOT NULL AND pdate > '03-20-2012'