The "nested while loops" are a non-issue in terms of the overall performance of the code. They are a really inefficient way of emptying arrays, but in the context of the database I/O they are totally insignificant. The code complexity is O(n).

There are nested for loops too which are more interesting, but they effectively add a fixed computational load per line so again the have no effect on the complexity.

Perl is the programming world's equivalent of English

In reply to Re^2: Perl script speed by GrandFather
in thread Perl script speed by rr27

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