Using the Trakeva library, Ketrew can happily work with both Sqlite or Postgresql database backends.
The database is configured through the ~database_parameters argument of the
function Ketrew.Configuration.engine.
The default is to configure a Sqlite backend (which has then to be available), but one can easily use a Postgresql database by passing a “conninfo” URI (cf. documentation).
Ketrew comes with a synchronization tool, see ketrew synchronize --help.
One can copy the data between databases:
ketrew sync --from sqlite:///path/to/the/db --to postresql://pg@example.com/databasename?password=blablaOr use “backup” directory trees:
ketrew sync --from sqlite:///path/to/the/db --to backup://path/to/backupor
ketrew sync --from backup://path/to/backup --to postresql://pg@example.com/databasename?password=blablaThe backup directory contains a few directories, containing each a number of JSON files.