Thanks a lot to everyone. Especially the links were helpful.

It looks like I have to do as much copying operations as I expected.
But the hints you gave me give my code more perlish elegance.

Pustular Postulant is right, the records are much larger than the keys - but rethinking it - the records are just stored as pointers in a hash of hashes. So copying them won't hurt that much

In reply to Re^4: sorting a hash by Ben Win Lue
in thread sorting a hash by Ben Win Lue

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