[GENERAL] Wiki consisting of rows in a db table

Consider a wiki that lets you edit rows in a db table. Each page is a row in the table, and has fields that anyone can edit. Like all wikis, it keeps a history of edits (including who made the edits), and lets you revert an edit, or even delete a row (page) completely. Has anyone implemented somet

[GENERAL] Upgrade db format without older version of PostgreSQL

I recently upgraded PostgreSQL, and now this happens: # /etc/init.d/postgresql start An old version of the database format was found. You need to upgrade the data format before using PostgreSQL. See /usr/share/doc/postgresql-8.3.8/README.rpm-dist for more information. Unfortunately, I upgraded d

[GENERAL] Viable alternatives to SQL?

Many sites let you search databases of information, but the search queries are very limited. I'm creating a site that'll allow arbitrary SQL queries to my data (I realize I'll need to handle injection attacks). Are there other viable ways to query data? I read a little on "Business System 12" (BS

[GENERAL] Efficiently storing a directed graph

I have a directed graph (nodes and edges) that I want to store "efficiently": given two nodes, I want to quickly find the shortest path between them. The graph is NOT acyclic (it's not a tree), is fairly "sparse" (about 1 edges for 2500 nodes), and changes occasionally. I know PostgreSQL/MySQL