facarroll Posted June 20, 2012 Share Posted June 20, 2012 I have the following SELECT statement that does not show an error, but it's not working correctly, either. I suspect the CASE is not correct, but where? $query = mysql_query("SELECT users.id, quiz.userId, quiz.family, quiz.quizTitle, quiz.userGroup, quiz.passState, SUM(CASE WHEN quiz.passState=1 THEN quiz.passState * '".$pass."' ELSE (quiz.passState+1) * '".$fail."' END) AS total FROM quiz, users WHERE quiz.userIdRec = users.id AND quiz.addDate BETWEEN '".$start_date."' AND '".$end_date."' AND users.egroup='".$egroup5."' AND quiz.managerId='".$userid."' GROUP BY quiz.userId, quiz.quizTitle ORDER BY quiz.family, quiz.addDate") or die(mysql_error()); The values for the variables are dates and simple numbers. Nothing wrong with those. I suspect the syntax SUM(CASE WHEN quiz.passState=1 THEN quiz.passState * '".$pass."' ELSE (quiz.passState+1) * '".$fail."' END) AS total . passState always has the value '1' or '0'. I want to be able to derive a value from each which is a product of (in the first case) passState by the value in $pass. In the second case, I also want to calculate a value based on passState when it = '0', by simply adding '1' and multiplying by the value contained in the variable $fail. Can anyone see what is wrong with the SELECT? Quote Link to comment Share on other sites More sharing options...
Barand Posted June 20, 2012 Share Posted June 20, 2012 SUM(CASE WHEN quiz.passState=1 THEN quiz.passState * '".$pass."' ELSE (quiz.passState+1) * '".$fail."' END) AS total Given that you are always multiplying by 1 SUM(CASE WHEN quiz.passState=1 THEN $pass ELSE $fail END) as total Quote Link to comment Share on other sites More sharing options...
facarroll Posted June 20, 2012 Author Share Posted June 20, 2012 I should have explained the situation better. The SELECT takes an existing student result to a quiz from the database where (passState will always equal either pass (1) or fail (0). I want to allocate a score to each result. The score can be any value for a pass and a different value for a fail. So passState being 1 can be multiplied by $pass to get a score. I want to be able to give a student a mark for attempting, even though he fails, So in this event, passState can be multiplied by $fail, but because it's value is already 0, I add 1 to passState to enable the multiplication. I hope this is clearer. Quote Link to comment Share on other sites More sharing options...
facarroll Posted June 20, 2012 Author Share Posted June 20, 2012 Oh my! I've just read your post more carefully. I couldn't see the forest for the trees. I'll test this, but I think it looks good. Why didn't I see that? Quote Link to comment Share on other sites More sharing options...
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