I have a fairly large table (~5 MB csv file) stored on our server that consists of purely numeric data giving some result based on two parameters, e.g.
A B Output
-----------------------
1 1 20
1 2 21
1 3 22
2 1 23
2 2 24
2 3 25
... ... ...
What I'd like to do is, based on the user's input, find the closest parameters then use the appropriate output. For example, using the table above, if the user select A=1.1 and B=2.9, the Output would be 22.
What is the best way to do this table lookup in php? Do I need to load the entire table into PHP? Instead of a csv-file, should I make it binary so that the file size is smaller and loads faster? Or should I create a mySQL database and perform a look-up that way?
TL;DR: I'm looking for the most efficient way to perform a nearest-neighbor table look-up on strictly numeric data.
If mysql is available, my suggestion would be to use a table and do a look up. I guess rounding the user input to the nearest integer before lookup should give you the closest.