Thanks for these sharp comments! I am glad to see perl gurus on this question.

I will try to implement this structure. Actually I don't need to retain the order between 2.1 and 2.2 for instance. Sorry if it was not clear enough!

If I use the fetchall_arrayref, maybe it is not worth to change this structure?
does perl spend a lot of resources to create a strucure?
Can I come back on this page to add new comments if I need help to implement it or to get some value? There is so much topics posted each day that I assume it is difficult to check if there is a new comment for an old node (except if you look carefully the newest nodes section)

thanks again.

In reply to Re^4: Best complex structure? by Anonymous Monk
in thread Best complex structure? by Anonymous Monk

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