im not a professional programmer, but already the idea of storing mass amounts of data you'll be accessing a lot in
a file on a hard drive... just makes me shiver =/
I'd recommend you sort it out with arrays, just think of an efficient way to handle it all, maybe you can omit some calculations
The current version of my biggest script keeps roughly a thousand values in arrays (probably even more), and it uses only about 11 MB of ram just after start (though it does leak up to about 70 MB, but thats a completely different story
)
Edit: i mean the server running the script takes that much ram, which almost equals the memory a clean server uses