Why is this Hive code returning 0 results?

Question

select * 
FROM prd_raw_sf.sf_opportunity_dn A JOIN 
     prd_raw_sf.sf_opportunity_rw B
     ON A.OPPORTUNITYID  = B.SFDC_ID LEFT JOIN
     prd_raw_sf.sf_si_accounts_mapping C
     ON TRIM(UPPER(A.ACCOUNT_NAME)) = TRIM(UPPER(C.sfdc_account_name))
WHERE C.sfdc_account_name IS NULL
and C.Billing_Client in ('CL.00000:')

It returns the necessary results when I query till "WHERE C.sfdc_account_name IS NULL". However, if I add the last line... "and C.Billing_Client in ('CL.00000:')", it just returns 0 result. Please help!

Answer 1

I speculate that you intend:

SELECT * 
FROM prd_raw_sf.sf_opportunity_dn od JOIN 
     prd_raw_sf.sf_opportunity_rw orw
     ON od.OPPORTUNITYID = orw.SFDC_ID LEFT JOIN
     prd_raw_sf.sf_si_accounts_mapping am
     ON TRIM(UPPER(od.ACCOUNT_NAME)) = TRIM(UPPER(ord.sfdc_account_name)) AND
        am.Billing_Client in ('CL.00000:')
WHERE am.sfdc_account_name IS NULL;

It is impossible for the account name to be NULL after the LEFT JOIN and for the Billing_Client to be anything other than NULL . That is because the account name is used as a JOIN key, so NULL does not match. The NULL value indicates no match, so all other columns from the table are NULL .

Note that I also fixed the table aliases so they are meaningful rather than arbitrary letters.