I would actually be fairly surprised if cacti could work well with a flat file structure. If you take a look at the code sometime (and even more so with 0.
, it is highly interwoven with SQL. Unless the PHP could create a near SQL92 compliant flat file interface, I doubt it would scale.
About the use of other SQL implementations, this *is* coming. In fact version 0.8 already makes use of ADODB. A friend of mine and I were working on porting the schema to MSSQL, but the cacti's code still needs some work. There are many places where I am directly referring to a MySQL function, which have to be replaced with their ADODB equivalents. Once that is out of the way, you should be able to use cacti with PostgreSQL, Access, MSSQL, MySQL, Oracle... the works