Thanks for all the responses. I actually need to compare data points not only across variables but across periods of time as well.

For example: Divide the data point for variable x on 1/1/2005 by the data point for variable x on 1/30/2005 and compare that to the same metric for variable y. I need to iterate through this algorithm for each day in the database.

I will therefore need to essentially constantly be polling the database for the datapoints associated with a particular day. I'm thinking that it is going to be much more efficient to load it all into hash structures at the outset and then just run a loop on those.

Do I need to have a separate hash structure setup for each variable (i.e. %variableone, %variabletwo, etc.) in order to access the information? (code example: $datapoint = $variableone{'1/20/05'). Is there some way I could setup a matrix like data structure in perl that would mimic an sql structure (code example: $datapoint = $data{'1/20/05'}->variableone )

Thanks.

In reply to Re^2: Efficient Data Comparison by Anonymous Monk
in thread Efficient Data Comparison by Anonymous Monk

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