From: | merlyn(at)stonehenge(dot)com (Randal L(dot) Schwartz) |
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To: | "Evandro's mailing lists (Please, don't send personal messages to this address)" <listasjr(at)gmail(dot)com> |
Cc: | pgsql-general <pgsql-general(at)postgresql(dot)org> |
Subject: | Re: Beyond the 1600 columns limit on windows |
Date: | 2005-11-08 13:30:07 |
Message-ID: | 867jbjgtcw.fsf@blue.stonehenge.com |
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Thread: | |
Lists: | pgsql-general |
>>>>> "Evandro's" == Evandro's mailing lists (Please, don't send personal messages to this address) <listasjr(at)gmail(dot)com> writes:
[I would have replied to your personal address, but I'm not about
to copy it from a footer.]
Evandro's> I'm doing a PhD in data mining and I need more than 1600 columns. I got an
Evandro's> error message saying that I can not use more than 1600 columns.
Evandro's> It is happening because I have to change categorical values to binary
Evandro's> creating new columns. Do you know if oracle can handle it?
/me boggles
You are doing a PhD in data mining, and you have a table that needs
more than 1600 columns?
/me gasps
What are they *teaching* these days?
If you have a design that has more than 20 or so columns, you're
probably already not normalizing properly. There just aren't *that*
many attributes of a object before you should start factoring parts of
it out, even if it means creating some 1-1 tables.
In programming, if I ever see someone name a sequence of variables,
like "thing1" and "thing2", I know there's going to be trouble ahead,
because that should have been a different data structure. Similarly,
I bet some of your columns are "foo1" and "foo2". Signs of brokenness
in the design.
Or do you really have 1600 *different* attributes, none of which have
a number in their name? That requires a serious amount of
creativity. :)
--
Randal L. Schwartz - Stonehenge Consulting Services, Inc. - +1 503 777 0095
<merlyn(at)stonehenge(dot)com> <URL:http://www.stonehenge.com/merlyn/>
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