Im a novice and many times I come up with alternatives that are not always the wisest way to go about something..

I need advise regarding how to save large quantity of records,(15.000 or so), that needs to be retrieved and changed often, (every 20 seconds or so), and dont how to install in my Windows PC, test my scripts, and run a proper MySQL or MySQL Lite database for development purposes or later move it to the server for final installation.

If I save each record in a single Flat File, it would need to be opened, read, and rewritten, which I assume is not the fastest technique.. If I save all records in a single flat file, (one record per line), reading the whole file into memory every 20 seconds and change what's needed may not be the best way to go either, (knowing there could be 15.000 lines or more...), so I 'm now contemplating something I read in the book entitled "I didnt know you could do that with perl", a technique of saving records in a flat file with SQL language in my perl script.

Has anyone done this, would this be fast and secure..??

Thanx beforehand
VirtualWeb ====================== ADDENDUM Sep 22nd THanx for all the great suggestions