Since you say that the file size has increased from 5 to 125MB, I'll just guess it won't stop there... So, yes, a Database would be the way to go.

If that is not feasible, you might want to create a sort-file from your original data that consists of the sorting criteria in a directly (ascii-)sortable fixed-length format starting at the beginning of the line and the original data afterwards, separated by a delimiter.
This file can then be sorted by any simple sort program. (if you're on a unix box or have cygwin available, 'sort' should do the job easily and you can tweak the buffer size it uses for optimum performance on your box. After all, sorting files is exactly what it was written for!)
After sorting, just filter out the sorting info and the delimiter again and you have your sorted data.

In reply to Re: Reducing Memory Usage by mhi
in thread Reducing Memory Usage by PerlingTheUK

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