Minor Description
In current implementation of DbImport attributes are loaded in batch for the catalog/schema. In some rare cases this could lead to problems if there's some weird schemas/access issues. And there's no way to tell what's wrong as we don't have any information on our end, just a failed request to load all DB columns.
We could add fallback option to load attributes on a per-entity level that could help at least to locate the problem if not completely avoid.