On 2016-03-25 Hartmut W Sager wrote:
First, a question: Do you want two separate X and Y counts for each customer, or a combined "X or Y" count for each customer?
Option 1
If the former, then I propose:
SELECT custid, sum(totx), sum(toty) FROM (SELECT custid, count(*) as totx, 0 as toty FROM ordertable WHERE TTL=X GROUP BY custid UNION SELECT custid, 0 as totx, count(*) as toty FROM ordertable WHERE TTL=Y GROUP BY custid) GROUP BY custid ORDER BY custid;
Ah! That's the trick! I was playing with unions and gave up because I was only trying: select a,b union select a,c
and getting frustrated that the final result wasn't giving me a,b,c but was instead putting c values into a b labelled column!
Your example by fudging 0 into the matching col name solves that!
That may indeed be the solution, I'm changing my code now. I was reluctant to use subselects because (while they are working now) I am actually pulling out 6 counts, sums and avgs in 6 subselects on where's matching 10,000+ rows, meaning the db computation time is not optimal.
Thanks!