A folder that's not a folder or a database

Sorry for the cryptic subject but it seems appropriate.

Over the last few days I have been asking some questions about accessing the Adobe Lightroom catalog and have received great help from everyone - thanks. I have been completely successful in gathering the info from the catalog except for one final piece - the jpeg image preview.

The LR catalog is composed of several files (only 2 unless LR is running, then there are several others). The 2 I am working with are the catalog file and the previews file. Example names would be MasterCatalog.lrdata and MasterCatalog Previews.lrdata. The first is just a regular SQLite database which I can open and read with no problem. The 2nd, previews.lrdata is a different animal. If I look at it with Finder, it’s just a file - Get Info Kind says Adobe Lightroom Data. I use Base to work with SQL files outside of Xojo - if I ctrl-click on the file and say open with Base, I get an error that says the file is encrypted or is not a database. If I use the Base Open File dialog and browse to the profiles.lrdata file it now appears as a folder with other files inside. Two of them are database files which I can then open and read with Base - they are called profiles.db and rootPixels.db.

The folks on the Adobe Lightroom SDK forum pointed me to a couple of resources which I am pursuing but I wanted to ask the folks here because I always get useful answers. But one user said the previews.lrdata isn’t a database (kinda obvious) but was a “sequence of folders” - whatever that exactly means.

Can anyone suggest how I might be able to get inside previews.lrdata and open the 2 .db files inside within Xojo?

Any help is GREATLY appreciated.

It sounds like that is a Document Package. I would think you can just treat it as a folder as far as Xojo is concerned to get at the files it contains.