Hi,
Have you considered maybe ltree datatype? http://www.postgresql.org/docs/9.1/static/ltree.html I think it solves a lot of problems in topic.... Kind regards, Misa On Friday, February 15, 2013, Don Parris wrote: > Hi all, > > I posted to this list some time ago about working with a hierarchical > category structure. I had great difficulty with my problem and gave up > for a time. I recently returned to it and resolved a big part of it. I > have one step left to go, but at least I have solved this part. > > Here is the original thread (or one of them): > > http://www.postgresql.org/message-id/CAJ-7yonw4_qDCp-ZNYwEkR2jdLKeL8nfGc+-TLLSW=rmo1v...@mail.gmail.com > > Here is my recent blog post about how I managed to show my expenses summed > and grouped by a mid-level category: > http://dcparris.net/2013/02/13/hierarchical-categories-rdbms/ > > > Specifically, I wanted to sum and group expenses according to categories, > not just at the bottom tier, but at higher tiers, so as to show more > summarized information. A CEO primarily wants to know the sum total for > all the business units, yet have the ability to drill down to more detailed > levels if something is unusually high or low. In my case, I could see the > details, but not the summary. Well now I can summarize by what I refer to > as the 2nd-level categories. > > Anyway, I hope this helps someone, as I have come to appreciate - and I > mean really appreciate - the challenge of working with hierarchical > structures in a 2-dimensional RDBMS. If anyone sees something I should > explain better or in more depth, please let me know. > > Regards, > Don > -- > D.C. Parris, FMP, Linux+, ESL Certificate > Minister, Security/FM Coordinator, Free Software Advocate > http://dcparris.net/ > <https://www.xing.com/profile/Don_Parris><http://www.linkedin.com/in/dcparris> > GPG Key ID: F5E179BE >
