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Archives of the TeradataForum
Message Posted: Tue, 26 Mar 2002 @ 22:43:09 GMT
Subj: | | Re: Table partitioning |
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From: | | John K. Wight |
Why play the DBA partitioning game that you have to in so many other DBMS's with date partitioning, etc.? Now you have a bunch of 'data
barrels'. Each data barrel might give you good performance for that 'barrel' but as you said, when you want to see more than one barrel at
a time - you now have to UNION them in views and when you do that you discard some of the more important underlying mechanisms. Also, try
joining a view that UNIONs two or more in one view with other tables/views! That's a fun one to see the EXPLAINS on. You will then figure
out you'll have to do the all the joins separately before you UNION them thus making multiple passes of the other tables in many cases, etc.
etc. etc.
Teradata is really good at keeping all the data in one place and partitioning it this way doesn't really make since in the long run.
Your SQL is more complicated, your plans will suffer, your maintenance will also be more complex, etc. etc.
I believe that Neil hit it on the head in the first part of his assessment - from my view anyway (for what it is worth on the open market
these days)!
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