docs: function _checkConnection(conn) {
    // Return Promise for getConnection callback wrapping
    return new Promise((resolve, reject) => {
      if (conn) {
        resolve(conn);
      } else {
        _pool.getConnection((err, conn) => {
          if (err) reject(err); // Reject this error
          else resolve(conn); // Resolve the connection
        })
      }
    });
  }