prepare('SELECT * FROM tenants WHERE id = :id'); $stmt->execute(['id' => $id]); return $stmt->fetch() ?: null; } function getTenantByUsername(PDO $db, string $username): ?array { $stmt = $db->prepare('SELECT * FROM tenants WHERE username = :u'); $stmt->execute(['u' => $username]); return $stmt->fetch() ?: null; } function tenantCount(PDO $db): int { return (int)$db->query('SELECT COUNT(*) FROM tenants')->fetchColumn(); } function adminCount(PDO $db): int { return (int)$db->query('SELECT COUNT(*) FROM tenants WHERE is_admin = 1')->fetchColumn(); }