[dataimport] fix db-namespace default value handling In a fresh new instance, the "db-namespace" option is set as empty by default in the "sources" file. This seems correct but empty string is not a valid pg_schema and actually means that we should use "public"

.. _cwprops:

The property mecanism
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.. XXX CWProperty and co


Property API
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.. XXX feed me

Registering and using your own property
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.. XXX feed me