After looking at the initial brief for Total ReCal, we realised that it would be necessary to build a new data storage layer to handle the time/space information which drives the project. There are many reasons for this both technical and political, but the key reason is that since we are running what is effectively an abstraction and amalgamation service we want to be able to interface directly with our own copy of the data; here’s why.
Speed is often considered a luxury when dealing with large data sets, and especially in larger institutions it’s common to think nothing of waiting a few minutes for a report to finish building or for your operation to finish processing, but we wanted to offer something where you could happily hit it with 20-30 queries a second over an API. This is particularly relevant given our larger Nucleus un-project to expose public (and some private) data over APIs to allow mashups. In short, we don’t want to have to wait for even half a second whilst another service gets the data we’re after, and we especially don’t want to have to waste more time parsing the data into a useful format.
We looked at several possibilities for how to store the data. An obvious one to take a look at is a traditional RDBMS1 such as PostgreSQL or MS-SQL. In this instance we would most likely have been using MySQL, since it fits smoothly into the almost universally supported LAMP2 stack which is available on our key development server. Alex and myself are both well-versed in using MySQL as a database and interfacing with it using PHP, so should we have opted for an RDBMS it would be the obvious choice despite the rest of the University standardising on MS-SQL.