Question

I have the following query:

    SELECT  PROGID1 = P.Prog, ENTERDATE1 = MAX(ENTERDATE), 
    BANKID = (select B.BANKID from BANK B
              WHERE B.ID = PROGID1 and B.ENTERDATE = ENTERDATE1 
             )  
   FROM PROTOCOL P JOIN BANK B ON P.ID = B.ID 
   group by P.ID  

What I need to do is to get the BANKID for a given MAX(ENTERDATE) but as BANKID has duplicate records, I need to find it based on what the MAX ENTERDATE
was. I tried to do the following but I get a message saying invalid column name PROGID1 and ENTERDATE1 inside of:

    (select B.BANKID from BANK B
     WHERE B.ID = PROGID1 and B.ENTERDATE = ENTERDATE1 
              )  

Answer 1

Something like this? I.e., use the “protocol” query as a table.

SELECT b.bank_id
  FROM bank b
     , ( SELECT id AS progid1, MAX(enterdate) AS enterdate1
           FROM protocol
          GROUP BY prog
       ) p
 WHERE b.id = p.progid1
   AND b.enterdate = p.enterdate1

P.S. I think you used “p.prog” where you meant p.id.