Oracle FAQ Your Portal to the Oracle Knowledge Grid
HOME | ASK QUESTION | ADD INFO | SEARCH | E-MAIL US
 

Home -> Community -> Mailing Lists -> Oracle-L -> RE: Reorganizing tables

RE: Reorganizing tables

From: Khedr, Waleed <Waleed.Khedr_at_FMR.COM>
Date: Mon, 24 Mar 2003 19:40:23 -0500
Message-Id: <24765.322951@fatcity.com>


This message is in MIME format. Since your mail reader does not understand this format, some or all of this message may not be legible.

------=_NextPartTM-000-9d75928c-56f0-4948-9e54-98502dd9f640 Content-Type: multipart/alternative;

        boundary="----_=_NextPart_001_01C2F267.1EC86CC0"

------_=_NextPart_001_01C2F267.1EC86CC0
Content-Type: text/plain

 oerr ora 14642

14642, 00000, "Bitmap index mismatch for tables in ALTER TABLE EXCHANGE PARTITION"
// *Cause: The two tables in the EXCHANGE have usable bitmap indexes, and the
// INCLUDING INDEXES option has been specified and the tables have
// different hakan factors.

// *Action: Perform the exchange with the EXCLUDING INDEXES option or alter the
// bitmap indexes to be unusable.

oerr ora 14643

14643, 00000, "Hakan factor mismatch for tables in ALTER TABLE EXCHANGE PARTITION"
// *Cause: Either records_per_block has been minimized for one of the tables to be
// exchanged, but not the other, or the hakan factors for the
tables to be
// exchanged are not equal.

// *Action: If records_per_block has been minimized for one of the tables, but not
// the other, either perform alter table with the NOMINIMIZE
RECORDS_PER_BLOCK
// option for both tables, or perform alter table with the MINIMIZE
// RECORDS_PER_BLOCK for both tables. If the hakan factors do not
match
// perform alter table with the NOMINIMIZE RECORDS_PER_BLOCK option
// for both tables.

-----Original Message-----
From: Jared.Still_at_radisys.com [ <mailto:Jared.Still_at_radisys.com> mailto:Jared.Still_at_radisys.com]
Sent: Monday, March 24, 2003 6:34 PM
To: Multiple recipients of list ORACLE-L Subject: Re: Reorganizing tables

Jonathan,

What is the 'Haken' factor?

Jared

"Jonathan Lewis" <jonathan_at_jlcomp.demon.co.uk> Sent by: root_at_fatcity.com
 03/24/2003 02:24 PM
 Please respond to ORACLE-L

        To:     Multiple recipients of list ORACLE-L <ORACLE-L_at_fatcity.com>
        cc:
        Subject:        Re: Reorganizing tables



This may have been mentioned already, but a table re-org can be a positive threat to performance.

If your primary tables have (for example) a three-stage life:

    initial row size is small
    row grows after a couple of weeks
    row reaches full size after another 4 weeks, then what value are you going to use for your PCTFREE when you rebuild ?

If you set it to zero to avoid wasting space for the vast percentage of rows that are full size then many incomplete rows will end up migrating.

If you set it to match the growth requirement of the newest rows, then you leave lots of empty space in the blocks that hold only old rows.

(The optimum storage answer is to set the Hakan factor before moving the table - but that's not a trivial exercise because of a bug whose number I can't remember).

Regards

Jonathan Lewis
 <http://www.jlcomp.demon.co.uk> http://www.jlcomp.demon.co.uk

For one-day tutorials:
(see <http://www.jlcomp.demon.co.uk/tutorial.html> http://www.jlcomp.demon.co.uk/tutorial.html )

____UK_______April 8th
____UK_______April 22nd
____Denmark May 21-23rd
____USA_(FL)_May 2nd

Next dates for the 3-day seminar:
(see <http://www.jlcomp.demon.co.uk/seminar.html> http://www.jlcomp.demon.co.uk/seminar.html )

____UK_(Manchester)_May
____Estonia___June (provisional)
____USA_(CA, TX)_August

The Co-operative Oracle Users' FAQ
 <http://www.jlcomp.demon.co.uk/faq/ind_faq.html> http://www.jlcomp.demon.co.uk/faq/ind_faq.html

> Thanks Jared, Rachel, Tom, Dick, Prakash, Ron
>
> Excellent points. Very much appreciated. Unfortunately at this point
people
> are asking "but have you tested it?". So I need to construct some type of
> test that will demonstrate how much effect a reorg will have. After I've
> answered that question, then I can move on to some of the other issues that
> you mention. I have joked that if the results are strongly positive, they
> won't see me much after that because I'll be touring the world selling my
> performance solution that never occurred to anyone else. > Our test system is cloned from an RMAN backup of production so the tables
> should be close to production. I'm thinking of creating a new table and
> copying the contents of a production table into it and then tracing
> full-table scans and comparing the results.
>
> Jared - is there a way to estimate block-level fragmentation?
Comparing the
> average row length with the number of blocks used?
>
> Dennis Williams
> DBA, 40%OCP, 100% DBA
> Lifetouch, Inc.
> dwilliams_at_lifetouch.com



--
Please see the official ORACLE-L FAQ:  <http://www.orafaq.net>
http://www.orafaq.net
--
Author: Jonathan Lewis
  INET: jonathan_at_jlcomp.demon.co.uk

Fat City Network Services    -- 858-538-5051  <http://www.fatcity.com>
http://www.fatcity.com
San Diego, California        -- Mailing list and web hosting services
---------------------------------------------------------------------
To REMOVE yourself from this mailing list, send an E-Mail message
to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in
the message BODY, include a line containing: UNSUB ORACLE-L
(or the name of mailing list you want to be removed from).  You may
also send the HELP command for other information (like subscribing).




--
Please see the official ORACLE-L FAQ:  <http://www.orafaq.net>
http://www.orafaq.net
--
Author:
  INET: Jared.Still_at_radisys.com

Fat City Network Services    -- 858-538-5051  <http://www.fatcity.com>
http://www.fatcity.com
San Diego, California        -- Mailing list and web hosting services
---------------------------------------------------------------------
To REMOVE yourself from this mailing list, send an E-Mail message
to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in
the message BODY, include a line containing: UNSUB ORACLE-L
(or the name of mailing list you want to be removed from).  You may
also send the HELP command for other information (like subscribing).



------_=_NextPart_001_01C2F267.1EC86CC0
Content-Type: text/html

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML><HEAD>
<META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=US-ASCII">
<TITLE></TITLE>

<META content="MSHTML 5.50.4923.2500" name=GENERATOR></HEAD>
<BODY>
<P><FONT size=2><FONT face="Courier New"><U>&nbsp;oerr ora 
14642</U></FONT></FONT></P><FONT size=2><FONT face="Courier New"><U></U>
<P><BR>14642, 00000, "Bitmap index mismatch for tables in ALTER TABLE EXCHANGE 
PARTITION"<BR>// *Cause:&nbsp; The two tables in the EXCHANGE have usable bitmap 
indexes, and the<BR>//&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
INCLUDING INDEXES option has been specified and the tables 
have<BR>//&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; different hakan 
factors.<BR>// *Action: Perform the exchange with the EXCLUDING INDEXES option 
or alter the<BR>//&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; bitmap 
indexes to be unusable.<BR></P>
<P><BR><U>oerr ora 14643</U></P>
<P><BR>14643, 00000, "Hakan factor mismatch for tables in ALTER TABLE EXCHANGE 
PARTITION"<BR>// *Cause:&nbsp; Either records_per_block has been minimized for 
one of the tables to 
be<BR>//&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; exchanged, but 
not the other, or the hakan factors for the tables to 
be<BR>//&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; exchanged are not 
equal.<BR>// *Action: If records_per_block has been minimized for one of the 
tables, but not<BR>//&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; the 
other, either perform alter table with the NOMINIMIZE 
RECORDS_PER_BLOCK<BR>//&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
option for both tables, or perform alter table with the 
MINIMIZE<BR>//&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
RECORDS_PER_BLOCK for both tables.&nbsp; If the hakan factors do not 
match<BR>//&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; perform alter 
table with the NOMINIMIZE RECORDS_PER_BLOCK 
option<BR>//&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; for both 
tables.<BR></FONT><BR>-----Original Message-----<BR>From: 
Jared.Still_at_radisys.com [</FONT><A href="mailto:Jared.Still_at_radisys.com"><FONT 
size=2>mailto:Jared.Still_at_radisys.com</FONT></A><FONT size=2>]<BR>Sent: Monday, 
March 24, 2003 6:34 PM<BR>To: Multiple recipients of list ORACLE-L<BR>Subject: 
Re: Reorganizing tables<BR><BR><BR>Jonathan,<BR><BR>What is the 'Haken' 
factor?<BR><BR>Jared<BR><BR><BR><BR><BR><BR><BR>"Jonathan Lewis" 
&lt;jonathan_at_jlcomp.demon.co.uk&gt;<BR>Sent by: 
root_at_fatcity.com<BR>&nbsp;03/24/2003 02:24 PM<BR>&nbsp;Please respond to 
ORACLE-L<BR><BR><BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
To:&nbsp;&nbsp;&nbsp;&nbsp; Multiple recipients of list ORACLE-L 
&lt;ORACLE-L_at_fatcity.com&gt;<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
cc:<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
Subject:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Re: Reorganizing 
tables<BR><BR><BR><BR>This may have been mentioned already, but a<BR>table 
re-org can be a positive threat to performance.<BR><BR>If your primary tables 
have (for example) a three-stage<BR>life:<BR>&nbsp;&nbsp;&nbsp; initial row size 
is small<BR>&nbsp;&nbsp;&nbsp; row grows after a couple of 
weeks<BR>&nbsp;&nbsp;&nbsp; row reaches full size after another 4 weeks,<BR>then 
what value are you going to use for your<BR>PCTFREE when you rebuild ?<BR><BR>If 
you set it to zero to avoid wasting space<BR>for the vast percentage of rows 
that are full<BR>size then many incomplete rows will end 
up<BR>migrating.<BR><BR>If you set it to match the growth requirement<BR>of the 
newest rows, then you leave lots of<BR>empty space in the blocks that hold only 
old<BR>rows.<BR><BR>(The optimum storage answer is to set the<BR>Hakan factor 
before moving the table - but<BR>that's not a trivial exercise because of a 
bug<BR>whose number I can't remember).<BR><BR><BR>Regards<BR><BR>Jonathan 
Lewis<BR></FONT><A target=_blank href="http://www.jlcomp.demon.co.uk"><FONT 
size=2>http://www.jlcomp.demon.co.uk</FONT></A><BR><BR><FONT size=2>For one-day 
tutorials:<BR>(see </FONT><A target=_blank 
href="http://www.jlcomp.demon.co.uk/tutorial.html"><FONT 
size=2>http://www.jlcomp.demon.co.uk/tutorial.html</FONT></A><FONT size=2> 
)<BR><BR>____UK_______April 8th<BR>____UK_______April 22nd<BR>____Denmark May 
21-23rd<BR>____USA_(FL)_May 2nd<BR><BR>Next dates for the 3-day seminar:<BR>(see 
</FONT><A target=_blank href="http://www.jlcomp.demon.co.uk/seminar.html"><FONT 
size=2>http://www.jlcomp.demon.co.uk/seminar.html</FONT></A><FONT size=2> 
)<BR>____UK_(Manchester)_May<BR>____Estonia___June (provisional)<BR>____USA_(CA, 
TX)_August<BR><BR>The Co-operative Oracle Users' FAQ<BR></FONT><A target=_blank 
href="http://www.jlcomp.demon.co.uk/faq/ind_faq.html"><FONT 
size=2>http://www.jlcomp.demon.co.uk/faq/ind_faq.html</FONT></A><BR><BR><BR><FONT 
size=2>----- Original Message -----<BR>To: "Multiple recipients of list 
ORACLE-L" &lt;ORACLE-L_at_fatcity.com&gt;<BR>Sent: 24 March 2003 
20:53<BR><BR><BR>&gt; Thanks Jared, Rachel, Tom, Dick, Prakash, 
Ron<BR>&gt;<BR>&gt; Excellent points. Very much appreciated. Unfortunately at 
this point<BR>people<BR>&gt; are asking "but have you tested it?". So I need to 
construct some<BR>type of<BR>&gt; test that will demonstrate how much effect a 
reorg will have. After<BR>I've<BR>&gt; answered that question, then I can move 
on to some of the other<BR>issues that<BR>&gt; you mention. I have joked that if 
the results are strongly positive,<BR>they<BR>&gt; won't see me much after that 
because I'll be touring the world<BR>selling my<BR>&gt; performance solution 
that never occurred to anyone else.<BR>&gt;&nbsp;&nbsp;&nbsp; Our test system is 
cloned from an RMAN backup of production so<BR>the tables<BR>&gt; should be 
close to production. I'm thinking of creating a new table<BR>and<BR>&gt; copying 
the contents of a production table into it and then tracing<BR>&gt; full-table 
scans and comparing the results.<BR>&gt;<BR>&gt; Jared - is there a way to 
estimate block-level fragmentation?<BR>Comparing the<BR>&gt; average row length 
with the number of blocks used?<BR>&gt;<BR>&gt; Dennis Williams<BR>&gt; DBA, 
40%OCP, 100% DBA<BR>&gt; Lifetouch, Inc.<BR>&gt; 
dwilliams_at_lifetouch.com<BR><BR><BR><BR>--<BR>Please see the official ORACLE-L 
FAQ: </FONT><A target=_blank href="http://www.orafaq.net"><FONT 
size=2>http://www.orafaq.net</FONT></A><BR><FONT size=2>--<BR>Author: Jonathan 
Lewis<BR>&nbsp; INET: jonathan_at_jlcomp.demon.co.uk<BR><BR>Fat City Network 
Services&nbsp;&nbsp;&nbsp; -- 858-538-5051 </FONT><A target=_blank 
href="http://www.fatcity.com"><FONT 
size=2>http://www.fatcity.com</FONT></A><BR><FONT size=2>San Diego, 
California&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; -- Mailing list and web 
hosting 
services<BR>---------------------------------------------------------------------<BR>To 
REMOVE yourself from this mailing list, send an E-Mail message<BR>to: 
ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in<BR>the message 
BODY, include a line containing: UNSUB ORACLE-L<BR>(or the name of mailing list 
you want to be removed from).&nbsp; You may<BR>also send the HELP command for 
other information (like subscribing).<BR><BR><BR><BR><BR>--<BR>Please see the 
official ORACLE-L FAQ: </FONT><A target=_blank 
href="http://www.orafaq.net"><FONT 
size=2>http://www.orafaq.net</FONT></A><BR><FONT size=2>--<BR>Author:<BR>&nbsp; 
INET: Jared.Still_at_radisys.com<BR><BR>Fat City Network Services&nbsp;&nbsp;&nbsp; 
-- 858-538-5051 </FONT><A target=_blank href="http://www.fatcity.com"><FONT 
size=2>http://www.fatcity.com</FONT></A><BR><FONT size=2>San Diego, 
California&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; -- Mailing list and web 
hosting 
services<BR>---------------------------------------------------------------------<BR>To 
REMOVE yourself from this mailing list, send an E-Mail message<BR>to: 
ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in<BR>the message 
BODY, include a line containing: UNSUB ORACLE-L<BR>(or the name of mailing list 
Received on Mon Mar 24 2003 - 18:40:23 CST

Original text of this message

HOME | ASK QUESTION | ADD INFO | SEARCH | E-MAIL US