Is oracle the only database that is good at keeping the number of levels in
an index to a minimum? Or is it common amongst the other major dbms?
----- Original Message -----
From: "Cary Millsap" <cary.millsap_at_hotsos.com>
To: <oracle-l_at_freelists.org>
Sent: Thursday, February 05, 2004 11:04 PM
Subject: RE: How does Oracle keep B-tree indexes to 3 levels?
> You get a new level only if the parent node splits propagate all the way
> to the index root node. Jonathan Lewis and Steve Adams have some good
> tests in their courses that use block dumps to show how Oracle
> redistributes keys in branch blocks when nodes split.
>
> Yes, Oracle index nodes are one block apiece.
>
>
> Cary Millsap
> Hotsos Enterprises, Ltd.
> http://www.hotsos.com
> * Nullius in verba *
>
> Upcoming events:
> - Performance Diagnosis 101: 2/24 San Diego, 3/23 Park City, 4/6 Seattle
> - SQL Optimization 101: 2/16 Dallas
> - Hotsos Symposium 2004: March 7-10 Dallas
> - Visit www.hotsos.com for schedule details...
>
>
> -----Original Message-----
> From: oracle-l-bounce_at_freelists.org
> [mailto:oracle-l-bounce_at_freelists.org] On Behalf Of Ryan
> Sent: Thursday, February 05, 2004 9:32 PM
> To: oracle-l_at_freelists.org
> Subject: How does Oracle keep B-tree indexes to 3 levels?
>
> I'm taking an academic database class. My professor showed us that when
> you have a block split and the parent node(s) split, you end up with a
> new level. I'm assuming oracle 'redistributes' the pointers instead of
> adding a new level?
> Are index nodes always one block?
> ----------------------------------------------------------------
> Please see the official ORACLE-L FAQ: http://www.orafaq.com
> ----------------------------------------------------------------
> To unsubscribe send email to: oracle-l-request_at_freelists.org
> put 'unsubscribe' in the subject line.
> --
> Archives are at http://www.freelists.org/archives/oracle-l/
> FAQ is at http://www.freelists.org/help/fom-serve/cache/1.html
> -----------------------------------------------------------------
>
> ----------------------------------------------------------------
> Please see the official ORACLE-L FAQ: http://www.orafaq.com
> ----------------------------------------------------------------
> To unsubscribe send email to: oracle-l-request_at_freelists.org
> put 'unsubscribe' in the subject line.
> --
> Archives are at http://www.freelists.org/archives/oracle-l/
> FAQ is at http://www.freelists.org/help/fom-serve/cache/1.html
> -----------------------------------------------------------------
Please see the official ORACLE-L FAQ:
http://www.orafaq.com
To unsubscribe send email to: oracle-l-request_at_freelists.org
put 'unsubscribe' in the subject line.
--
Archives are at http://www.freelists.org/archives/oracle-l/
FAQ is at http://www.freelists.org/help/fom-serve/cache/1.html
-----------------------------------------------------------------
Received on Thu Feb 05 2004 - 22:10:15 CST
