message: add the console msg
diff: @@ -580,7 +580,16 @@ void single_cmd()
  #endif //#ifdef _GCONSOLE_DEBUG
  {
  - volatile ReadlineWrapper rl(in_readline, line, "gstore> ");
  + string msg = "";
  + if (current_database == NULL)
  + {
  + msg = "gstore[no database]> ";
  + }
  + else
  + {
  + msg = "gstore[" + current_database->getName() + "]> ";
  + }
  + volatile ReadlineWrapper rl(in_readline, line, msg.c_str());
  }
  #ifdef _GCONSOLE_TRACE
  @@ -1461,9 +1470,12 @@ int raw_sparql_handler(string query)
  // }
  long tv_begin = Util::get_cur_time();
  int ret;
  - try {
  + try
  + {
  ret = current_database->query(query, _rs, ofp, true, export_flag, nullptr);
  - } catch (const std::exception &e) {
  + }
  + catch (const std::exception &e)
  + {
  cout << "Exception: " << e.what() << endl;
  return -1;
  }
  @@ -1822,7 +1834,10 @@ int show_handler(const vector<string> &args)
  rows.push_back({"built_time", built_time});
  }
  rows.push_back({"triple_num", Util::int2string(db->getTripleNum())});
  - rows.push_back({"entity_num", Util::int2string(db->getEntityNum()),});
  + rows.push_back({
  + "entity_num",
  + Util::int2string(db->getEntityNum()),
  + });
  rows.push_back({"literal_num", Util::int2string(db->getLiteralNum())});
  rows.push_back({"subject_num", Util::int2string(db->getSubNum())});
  rows.push_back({"predicate_num", Util::int2string(db->getPreNum())});
  