I run mysql and have dealt a little with memcahed stuff for a ticketing database. The problems facebook might have depends of which data storage engine they run, likely innodb, which are huge relational glop files. I run myisam tables for speed and because I’m only dealing with a gigabyte of data.
But yes, switching to another database would require a very bug prone rewrite with many database quirks. The language (SQL) is not consistently implemented from database maker to database maker and the connectors are inconsistent. They’d also be stuck with an oracle or sqlserver license fee out the wazoo.
All that for ten people? Wow.
I worked at a pharmacy benefits company with a comprehensive system that managed cardholders, drugs, plans, prior authorizations, etc. I wrote the data dictionary for the system which consisted of about 200-250 tables for various purposes. Some of the logic was kludgey, some of it was pretty ingenious. It was created in Oracle and scalability never seemed to be a problem. I would guess they managed about a million cardholders all told.
Oops, sorry my reply was meant for Kingu’s post number 10.
>>They’d also be stuck with an oracle or sqlserver license fee out the wazoo.
Is that last a specialized finance term?
;-P