Oh, yes and he is not using an RDMS either: just plain CSV-files!

How on earth do you know this?!? I've been following the thread and I haven't seen this tidbit. If so, I would assume the OP is using DBD::CSV, then. That's ... interesting. I wouldn't argue for it ... in fact, if there's any sort of reasonable work needing to be done in a reasonable time, porting to, at least, DBD::SQLite would be in order. Something that's written in optimized C as the engine for computationally-intensive bits is a must when doing any sort of serious work. This is why we don't use HTTP::Daemon when Apache/mod_perl is available.

Did you notice that he uses the LIKE-operator but does not include wildcards?

All that tells me is that the OP (and you) don't understand how DATEs work, especially in SQL. It is very expensive to convert a DATE to a CHAR, then perform a regex against it. Contrast that to using date arithmetic within the RDBMS, which is often optimized to use numeric vs. string comparisions.

The true solution is to fix the data source so that it's optimized to answer the question. Most RDBMSes will allow for a date to be "year-less", for just this type of query. Look it up.

Being right, does not endow the right to be rude; politeness costs nothing.
Being unknowing, is not the same as being stupid.
Expressing a contrary opinion, whether to the individual or the group, is more often a sign of deeper thought than of cantankerous belligerence.
Do not mistake your goals as the only goals; your opinion as the only opinion; your confidence as correctness. Saying you know better is not the same as explaining you know better.

In reply to Re^3: SQL ERROR by dragonchild
in thread SQL ERROR by WebDev

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