I do not think it is fair you load up your hash prior to the benchmarking, that skews the results.

Nor, is it fair that in the 'slow' one, you use a temporary array
my @items = split/,/,$_;
foreach my $item (@items){

[download]

vs
 foreach my $item (split/,/,$_){

[download]


Also, if ($choices{$item}) should probably be if (exists $choices{$item}) or you will choke on 0, empty strings, and undefs.

UPDATE:

Nor, is a grep a good idea, quoting a passage I remember reading in perldoc perlfaq: perldoc -q unique:
These are slow (grep) (checks every element even if the first matches), inefficient (same reason), and potentially buggy
But, granted it still says:
Hearing the word "in" is an indication that you probably should have used a hash, not a list or array, to store your data. Hashes are designed to answer this question quickly and efficiently. Arrays aren’t.


Evan Carroll
www.EvanCarroll.com

In reply to Re^2: Too much SQL not enough perl by EvanCarroll
in thread Too much SQL not enough perl by jcpunk

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