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So erhalten Sie die automatische Aktualisierung der SQL-WHERE-Anweisung vom Localhost-Link

Verwenden Sie diese Anweisung, um alle Schülerergebnisse Ihres Tests zu erhalten.

SELECT sq.stdid, sq.testid, COUNT(*) AS correctAnswers, 
SUM(q.marks) AS studentScore, (SELECT SUM(marks) FROM question 
WHERE testid=$_REQUEST['testid']) AS totalScore 
FROM question q, studentquestion sq 
WHERE sq.testid=$_REQUEST['testid'] AND q.testid = sq.testid 
AND q.qnid = sq.qnid AND sq.answered = 'answered' 
AND q.correctanswer = sq.stdanswer GROUP BY sq.stdid;

Sie können eine PHP-Variable erstellen, um den Prozentsatz zu berechnen. Beispiel:

$scorePercentage = $r3['studentScore'] / $r3['totalScore'] * 100;

oder

$scorePercentage = $r3['studentScore'] .'/'. $r3['totalScore'];

// Output: echo $scorePercentage;
60
60/100

Verwenden Sie diese SQL-Anweisung, um jetzt scorePercentage zu erhalten:
SELECT sq.stdid, sq.testid, COUNT(*) AS correctAnswers, 
(SUM(q.marks) / (SELECT SUM(marks) FROM question WHERE testid=1) * 100) 
AS studentScorePercentage FROM question q, studentquestion sq 
WHERE sq.testid=$_REQUEST['testid'] AND q.testid = sq.testid AND q.qnid = sq.qnid 
AND sq.answered = 'answered' AND q.correctanswer = sq.stdanswer 
GROUP BY sq.stdid;

SQLFiddle mit obigen Ergebnissen hier:http://sqlfiddle.com/#!9/8d47c/10