Question

I have a query that attempts to select cases/clients (clients.id) based on multiple conditions individually and as a group in two different tables (clients and referrals). >Since clients can have multiple referrals, I need the query to “loop” through each referral until two conditions are satisfied and then compare those results as a group against the third condition and return those cases only.
The problem is it is running through each condition separately even though they’re all >specified in the ‘where’. I’ve tried combining the conditions in the ‘c.id not in’ but still cannot get it to consider all conditions together.

To clarify some more:
I want referrals for cases/clients that satisfy these three conditions:

1. each referral is within a certain time frame (r.ReferralDate>=’2010-01-01′ and r.ReferralDate<=’2010-03-31′)
2. each referral is from any agency except agency 16, 17 and 19 (r.AgencyID<>16 and r.AgencyID<>17 and r.AgencyID<>19)
3. and ALL referrals for that case/client are successfully linked or referralcodeid = to 18

---

select c.id, c.lastname, c.firstname, a.AgencyLabel as 'Referral Made to:', r.ReferralDate, r.EligibilityDate, r.LinkageDate, r.ClosureDate, rc.referralcode 
from clients c
inner join referral r on c.id=r.ClientID
inner join agencies a on a.AgencyID=r.AgencyID
left outer join referralcodes rc on r.referralcodeid=rc.referralcodeid
where (r.ReferralDate>='2010-01-01' and r.ReferralDate<='2010-03-31')  
   and(r.AgencyID<>16 and r.AgencyID<>17 and r.AgencyID<>19) 
   and (c.id not in (select clientid from referral where referralcodeid <> 18))
   order by c.id

Been working on this for a while so any leads would be greatly appreciated!

Answer 1

Are you only wanting one case/client per row? Or one referral? Why wouldn’t all referrals have a referralcode? Etiher way I don’t think you need LEFT JOIN anyway.

SELECT * FROM client c
    JOIN referral r ON id=r.ClientID 
    JOIN agencies a USING(AgencyID) 
WHERE
     (r.ReferralDate >= '2010-01-01' and r.ReferralDate <='2010-03-31')
     AND r.AgencyID NOT IN(16,17,19)
     AND c.id NOT IN (SELECT ClientID FROM referral WHERE referrallcode <> 18 AND r.ReferralDate >= '2010-01-01' AND r.ReferralDate <='2010-03-31' )
GROUP BY c.id;

Take off GROUP BY if you want it by referral

Edit: Changed the check for the referral code to reflect the clarification by OP