Thanks a lot for your reply.
Without going into too much detail about algorithms or optimizers, the reflection was precisely about the subtle world to do things, do things right and make things better.

In detail, in my case, from a list of files (I did not need to open them) what occupy time were obviously the queries to a database on another server.
Cheer

In reply to Re^2: quickness is not so obvious by DanBev
in thread quickness is not so obvious by DanBev

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