Here's an example. The file names are version numbers based in hexadecimal. There is an xml that stores some version info. Not sure why they don't use the DB for this, maybe data integrity as most of this info is in the DB. Notice version 4 and 9 have a reference to 3 and 8. This was a datacard only version change so they don't copy the file and take up more space than needed.
Way better than than PDM/Works workgroup, which had no db and very limited functionality.
This is real PDM and is the primary application from SolidWorks. Smarteam is no longer sold. Enovia is 3dexperience rebranded. Of course Dassault would love everyone to go to 3dx but most companies don't want or need it.