If there are many queries are of the form "How many people are on at time x", it would pay to precompute the number of people online, second by second, and store this in a file to be accessed as needed. You could create a program to compute this incrementally and run a cron job periodically to update the file.

For the "How many people on between time x and y", I don't see any way around storing a list of begin-end pairs extracted from the weblogs and computing your functions from these.

For the math involved, you wish to consult some of the open source log analyzers, such as analog.

-Mark

In reply to Re: How to do session times The Right Way by kvale
in thread How to do session times The Right Way by strider corinth

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