Posts

Showing posts with the label Count

Conditional SQL Count

Answer : Use the aggregate FILTER option in Postgres 9.4 or later: SELECT category , count(*) FILTER (WHERE question1 = 0) AS zero , count(*) FILTER (WHERE question1 = 1) AS one , count(*) FILTER (WHERE question1 = 2) AS two FROM reviews GROUP BY 1; Details for the FILTER clause: Aggregate columns with additional (distinct) filters If you want it short : SELECT category , count(question1 = 0 OR NULL) AS zero , count(question1 = 1 OR NULL) AS one , count(question1 = 2 OR NULL) AS two FROM reviews GROUP BY 1; Overview over possible variants: For absolute performance, is SUM faster or COUNT? Proper crosstab query crosstab() yields the best performance and is shorter for longer lists of options: SELECT * FROM crosstab( 'SELECT category, question1, count(*) AS ct FROM reviews GROUP BY 1, 2 ORDER BY 1, 2' , 'VALUES (0), (1), (2)' ) AS ct (category text, zero int, one int, two int); Detailed explanation...

Conditional Count On A Field

Answer : I think you may be after select jobID, JobName, sum(case when Priority = 1 then 1 else 0 end) as priority1, sum(case when Priority = 2 then 1 else 0 end) as priority2, sum(case when Priority = 3 then 1 else 0 end) as priority3, sum(case when Priority = 4 then 1 else 0 end) as priority4, sum(case when Priority = 5 then 1 else 0 end) as priority5 from Jobs group by jobID, JobName However I am uncertain if you need to the jobID and JobName in your results if so remove them and remove the group by, Using COUNT instead of SUM removes the requirement for an ELSE statement: SELECT jobId, jobName, COUNT(CASE WHEN Priority=1 THEN 1 END) AS Priority1, COUNT(CASE WHEN Priority=2 THEN 1 END) AS Priority2, COUNT(CASE WHEN Priority=3 THEN 1 END) AS Priority3, COUNT(CASE WHEN Priority=4 THEN 1 END) AS Priority4, COUNT(CASE WHEN Priority=5 THEN 1 END) AS Priority5 FROM TableName GROUP BY jobId, jobName IIF is not a standard SQL construct...