RE: bitmap index Q.

I do this stuff for fun. :)

On Mon, 1 May 2000 Lisa_Koivu_at_gelco.com wrote:

> GOOD exercise? I had to do it in school, automatic balancing, etc. in C++
> You wanna talk about a nightmare... if it wasn't for the cute TA I would have
> never passed data structures!
>
> That's probably the ONE THING I learned studying CSCI that actually directly
> applies to my job.
>
>
>
>
>
>
>
> Jared Still <jkstill_at_bcbso.com> on 05/01/2000 01:00:32 PM
>
> Please respond to ORACLE-L_at_fatcity.com
>
> To: Multiple recipients of list ORACLE-L <ORACLE-L_at_fatcity.com>
> cc: (bcc: Lisa Koivu/GELCO)
>
>
>
>
>
>
> Hmm... That sounds like a good exercise.
>
> Time to break out the 'Data Structures' book, and put it in
> the queue with the other 20 or so books I'm supposed to read.
>
> Jared
>
> On Mon, 1 May 2000, I.S. Manager wrote:
>
> > Automatic tree-balancing is a basic feature of the btree algorithm. I wrote
> > a btree function once just to get a feel for what it does, and I can tell
> > you that it makes absolutely no difference whether the keys go in in
> > sequential, reverse-sequential, or random order.
> >
> >
> > At 02:49 PM 4/28/00 -0800, Jain, Akshay wrote:
> > >Is it true that if data is loaded in *sequential* order, with indexing on,
> > >the index gets lop sided. Thus only rebuilding the index(es) can
> > >restore its beneficial, shallow and wide structure.
> > >
> > >Unless there is automatic tree-balancing for indexes that Oracle
> > >does by itself?
> > >
> > >Akshay Jain
> > >_______________________
> > >Newcourt-CIT
> > >Tel. (416) 507-5385
> > >mailto:Akshay.Jain_at_cit.com
> > >_______________________
> > >
> > >
> > >-----Original Message-----
> > >Sent: Friday, April 28, 2000 3:54 PM
> > >To: Multiple recipients of list ORACLE-L
> > >
> > >
> > >Hola!
> > >
> > >One of our data marts here had awful performance yesterday. The only thing
> > >that
> > >was different between yesterday and the previous days was that the load ran
> > >with
> > >all indexes, including bitmaps, on the tables. Only 10,000 rows were added
> > >-
> > >less than 1% change. The analyze was run for all tables to be hit by the
> > >reports. However performance really bit yesterday until the indexes were
> > >dropped and rebuilt.
> > >
> > >In class I remember talking about the tradeoff between a fast load/building
> > >indexes and a slow load/leaving indexes up. Has anyone seen this type of
> > >behavior before? I can not say for sure that the load is not updating the
> > >fields the bitmap indexes were on.
> > >
> > >Any comments are appreciated.
> > >
> > >Lisa 'Almost Certified' Koivu
> > >
> > >
> > >
> > >--
> > >Author:
> > > INET: Lisa_Koivu_at_gelco.com
> > >
> > >Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051
> > >San Diego, California -- Public Internet access / Mailing Lists
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> > >(or the name of mailing list you want to be removed from). You may
> > >also send the HELP command for other information (like subscribing).
> > >--
> > >Author: Jain, Akshay
> > > INET: Akshay.Jain_at_cit.com
> > >
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> > >
> > >
> > ---
> > Dennis Taylor
> > ---
> > The opinions expressed herein are mine. Get your own opinions!
> > ---
> > --
> > Author: I.S. Manager
> > INET: ismgr_at_pctc.com
> >
> > Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051
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>
>
> Jared Still
> Certified Oracle DBA and Part Time Perl Evangelist ;-)
> Regence BlueCross BlueShield of Oregon
> jkstill_at_bcbso.com - Work - preferred address
> jkstill_at_teleport.com - private
>
>
> --
> Author: Jared Still
> INET: jkstill_at_bcbso.com
>
> Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051
> San Diego, California -- Public Internet access / Mailing Lists
> --------------------------------------------------------------------
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>
>
>
>
>
> --
> Author:
> INET: Lisa_Koivu_at_gelco.com
>
> Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051
> San Diego, California -- Public Internet access / Mailing Lists
> --------------------------------------------------------------------
> To REMOVE yourself from this mailing list, send an E-Mail message
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>

Jared Still
Certified Oracle DBA and Part Time Perl Evangelist ;-) Received on Mon May 01 2000 - 14:25:32 CDT