Retrieve data from corrupt catalog

First try the solution to create a 'light' copy of the corrupt catalog.

Create a new folder (anywhere) named something like 'My light catalog'.

From the corrupt catalog folder, copy the database file "catalog.pse18db" and copy it inside the "My light catalog' folder.

Double click that database file.

That will hopefully open the organizer with the light catalog. If it opens, you'll recover most of your organization, albums, keywords, captions and ratings, but nothing about face recognition or visual similarity.

Depending on the result, you might also try to keep the shift key pressed while navigating in the catalog manager to the new catalog folder; you might choose 'repair'. 

The above solution may work if the corruption does not affect the main database.

I only use an sqlite utility (database4.exe) to have a look at the contents of the catalogs. I very much doubt that you'll be able to extract albums data from corrupt catalogs.