[Improve]support one or more way of exporting and importing data

[PanternBao]

• dble version：
  2.19.05.0 or earlier

• limit：
  there are some problems when user use tools to export data from dble or import data to dble, eg: workbench,dbeaver,mysqldump,navicat,querybrowse...

• improve
  support one or more way of exporting and importing data

[PanternBao]

related issues:#877