lost image in some albums after upgrading from 2.2.4 to 2.2.5

I saw the following behavior after upgrading my gallery from 2.2.4 to 2.2.5:

Three of my albums seems to not contain any pictures anymore. But the albums tumbnail still show the picture of one of the images that was previously in my albums. After some investigation, I found out that the issue was that the images had no ownership any more.

Connect to your gallery DB and run the following query:
select * from g2_FileSystemEntity where g_id not in (select g_id from g2_Item);
if it return some row... you are probably in the same situation as I was.

To recover the situation, I did a merge between the g2_Item table that I had in the backup of the gallery 2.2.4 with the g2_Item table in my upgraded DB.

Is this a know issue? I didn't find any discussion directly related to this issue (...I also didn't spent hours time searching the forum

Where can I find a description of the Gallery DB? It would have make my troubleshooting easier.