Oh, I did almost the exact same thing once in an SQL database reporting system, brings back memories! /foo/*/blah/*/y We were putting very hierarchical data

Oh, I did almost the exact same thing once in an SQL database reporting system, brings back memories! /foo/*/blah/*/y We were putting very hierarchical data into a "flat" database, but we still wanted to be able to query on those deeply nested paths. At the time our front end used a lot of XSLT as well so it was a similar approach. Writing the library that turned these "special" queries back into SQL was one of the more fun engineering projects I ever worked on. Definitely wouldn't do it the same way today but for the project it was a good fit.