On 12-12-15 15:45, Luuk wrote: > > > On 12-12-15 15:18, Cecil Westerhof wrote: >> ?I have the following query: >> SELECT >> (SELECT COUNT(*) FROM proverbs) AS Total >> , (SELECT COUNT(*) FROM proverbs WHERE NOT used IS NULL) AS Used >> >> But I want something like: >> ? SELECT >> (SELECT COUNT(*) FROM proverbs) AS Total >> , (SELECT COUNT(*) FROM proverbs WHERE NOT used IS NULL) AS Used >> , (Total - Used) AS Free >> ?? >> ?But then I get: >> ? no such column: Total >> >> It can be done, because I have it done in the past, but obviously a >> little >> different. :'-( >> >> ?Anybody knows how it can be done?? >> > > > SELECT Total, Used, Total-Used as Free > FROM (SELECT (SELECT COUNT(*) > FROM proverbs) AS Total , > (SELECT COUNT(*) FROM proverbs WHERE NOT used IS NULL) AS Used)
or: select Total, Used, Total-Used as Free from (select count(*) as Total, count(used) as Used from proverbs)
