Re: oracle datamart - partioned views
Date: 1997/10/03
Message-ID: <3435B271.E6252983_at_erols.com.tyfns>#1/1
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Regarding your comment on Redbrick and ORACLE, I can provide scenarios where one significantly out performs the other for either prodcut. Each one has its advantages and disadvantages. To that point, I will only say, "When driving a nail use the hammer not the screw driver; when driving a screw use the screwdriver not the pliers."
I have used ORACLE in numerous data warehouses and data marts with great performance. Most performance issues are related to the data architecture and how it has been realized in the physical data base. Once those issues are corrected, if possible, the next issue is efficient SQL. Once this is done, I look at the combination of physical resources, such as memory, controllers, and disk usage along with tuning parameters. Even though there may be 1 Gb RAM (which is not much for a data mart or data warehouse server), how much is allocated to the instance? etc etc etc.
I do ORACLE performance tuning consulting work if you would like some professional assistance. Just reply to this email or call 804-262-6332.
Enjoy!
dgray_at_bdsinc.com wrote:
> Have a datamart (star scema) about 4M rows in the fact. Performance
>
> sucked, so I broke it into 8 tables and partioned viewed. they
> SUCK!
>
> I turned the ora.init parameter on.
> I constraied each table on the first part of the prim key. (time).
> I created a union all view.
> Oracle 7.3 HP 1 GB ram and 2 processors
>
> I then ran a query and - no matter the where clause it will hit
> every
> table. Even if I say where time_key = 3. No matter what. If the
> elimination of tables dosen't work then the benefits of severly
> minimined.
> True this will allow me to scan the table quicker (8x). But i need
>
> more!
>
> I'm running redbrick on the same box - ported the datamart over in 2
>
> hours. Redbrick kicks the crap out of oracle. Maybe oracle is not
> ready
> for warehousing! - I'm going to oracle 8 soon any body know if
> oracle 8
> is
> any better.
>
> I'm about to put oracle back in the box and burn it.
>
> I appreciate comments from anyone who has had partion view work to
> eliminate tables! or actually built a 'REAL' datamart in oracle and
> had
> oracles star execution path kick in w/o hints and had it return a
> result
> set in a reasonable time frame (< 15 secs).
>
> Thanks for any comments / knowledge!
> * please e-mail me with any info,
>
> Dave.
> dgray_at_bdsinc.com
>
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--------------6E249FFD6EF6E3EEB0D724CC-- Received on Fri Oct 03 1997 - 00:00:00 CEST