some relevant links: http://dwhoman.com/blog/sql-transitive-closure.html
http://charlesleifer.com/blog/querying-tree-structures-in-sqlite-using-python-and-the-transitive-closure-extension/ On Wed, 30 Jan 2019, 4:52 AM Bart Smissaert <bart.smissa...@gmail.com wrote: > Working on an Android app and part of that is storing SQL in a virtual > folder system in SQLite. For this I want to use a so-called closure table > as explained nicely here: > > http://technobytz.com/closure_table_store_hierarchical_data.html > > I have a table holder the folder details: > > ID PARENT_ID Folder > > ------------------------------------- > 1 0 Folder1 > 2 1 Folder2 > 3 1 Folder3 > 4 1 Folder4 > 5 2 Folder5 > 6 2 Folder6 > > > And then the closure table: > > PARENT_ID CHILD_ID DEPTH > > ----------------------------------------------- > 1 1 0 > 2 2 0 > 3 3 0 > 4 4 0 > 5 5 0 > 6 6 0 > 1 2 1 > 1 3 1 > 1 4 1 > 2 5 1 > 1 5 2 > 2 6 1 > 1 6 2 > > What should the SQL be to display the folders like this: > > Folder PARENT_ID > Folder1 0 > Folder2 1 > Folder5 2 > Folder6 2 > Folder3 1 > Folder4 1 > > > RBS > _______________________________________________ > sqlite-users mailing list > sqlite-users@mailinglists.sqlite.org > http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users > _______________________________________________ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
