[Feature Request] Import/export complete database including all schemas

I want to export /import the complete database but not even able to import/export more than 1 table. Only one table can be imported at a time. Weather we can export multiple tables at a time but if I try to export a schema then its not allowing me to do that.

The issue does not name any files, tests, or entry points. Start by locating the existing single-table import/export flow and determine how schema selection is represented. Done means importing and exporting a complete database, including multiple tables and all schemas, rather than only one table at a time.

Written by the indexing model from the issue text.