prepare("
SELECT username, class_handled
FROM teachers
WHERE id = ?
");
$stmt->execute([$_SESSION['teacher_id']]);
$teacher = $stmt->fetch(PDO::FETCH_ASSOC);
$class = $teacher['class_handled'];
/* Total */
$stmt = $pdo->prepare("SELECT COUNT(*) FROM students WHERE class = ?");
$stmt->execute([$class]);
$total_students = $stmt->fetchColumn();
/* Active */
$stmt = $pdo->prepare("
SELECT COUNT(DISTINCT pa.roll_no)
FROM practice_attempts pa
JOIN students s ON s.roll_no = pa.roll_no
WHERE s.class = ?
AND pa.last_attempt_at >= NOW() - INTERVAL 7 DAY
");
$stmt->execute([$class]);
$active = $stmt->fetchColumn();
/* Slowing */
$stmt = $pdo->prepare("
SELECT COUNT(DISTINCT pa.roll_no)
FROM practice_attempts pa
JOIN students s ON s.roll_no = pa.roll_no
WHERE s.class = ?
AND pa.last_attempt_at BETWEEN
NOW() - INTERVAL 10 DAY AND NOW() - INTERVAL 8 DAY
");
$stmt->execute([$class]);
$slowing = $stmt->fetchColumn();
/* Stalled */
$stmt = $pdo->prepare("
SELECT COUNT(*)
FROM (
SELECT pa.roll_no
FROM practice_attempts pa
JOIN students s ON s.roll_no = pa.roll_no
WHERE s.class = ?
GROUP BY pa.roll_no
HAVING MAX(pa.last_attempt_at) < NOW() - INTERVAL 10 DAY
) t
");
$stmt->execute([$class]);
$stalled = $stmt->fetchColumn();
?>
Reports