docs: function (conn, opts) {
              opts = opts || {};
              var s = opts.prepare, self = this;
              if (s) {
                  return this.__logConnectionExecute(conn, comb("XA END %s").format(this.literal(s))).chain(function () {
                      return self.__logConnectionExecute(comb("XA PREPARE %s").format(self.literal(s)));
                  });
              } else {
                  return this._super(arguments);
              }
          }