prepare($sql); $stmt->bind_param("ii", $analysisId, $compoundId); if ($stmt->execute()) { echo json_encode(['success' => true]); } else { echo json_encode(['success' => false, 'error' => 'Error adding compound association.']); } $stmt->close(); } else { echo json_encode(['success' => false, 'error' => 'Invalid input data.']); } $conn->close();