Hi and grazie for your reply! > If it's not an excercise, I think you don't need them Not an exercise - I have to use the VIEW though - this was only a sample. In real life the VIEW is trickier! > select (select count(*) from t1) / (select count(*) from t2)::float Looks as if the CAST was part of it. Check here: https://dbfiddle.uk/?rdbms=postgres_10&fiddle=9a15766de01946d7f57b4298d8fb1028 Thanks for your input! Pól...