RE: RMAN: What blocks are backed up with a full backup?
I partially agree with Mladen. RMAN definitely doesn't identify Table HWMs -- it doesn't know logical structures such as Tables and Segments and Tablespaces [although it can assist you in Tablespace Recovery when it reads the Data Dictionary]. RMAN knows physical structures such as DataFiles, RedoLog Files and ControlFiles. When backing up a DataFile, RMAN would ignore __unused__ blocks --- blocks that have never been used. Now, the part where I don't agree with Mladen is about reading the bitmap information from the tablespace header. RMAN can backup DataFiles belonging to Dictionary Managed Tablespaces without Automatic Segment Space Management. In such cases there is no bitmap in the tablespace header to read from. When Oracle creates a DataFile it initializes the file with NULLs. When a block is used [written to as a Table Row-Block or an Index Leaf-Block], the block has to be formatted before it is written-to. Once it is formatted [the formatting is the block header, table column names, and possibly the initrans area and pctfree area], the block will always remain used even if all the rows in it are deleted. Thus, when RMAN goes through a DataFile it examines each block and ignores unused blocks which have not been formatted. Such unused or empty blocks may be within an Extent or unallocated to any extent ! Hemant At 08:13 AM 04-04-03 -0800, you wrote: What it doesn't write are the blocks that are not allocated to any extent. RMAN doesn't go into the logical structures, like tables and indexes, it looks into the tablespace header and reads the information from the bitmap information there. It cannot go into tables/indexes because it should also work when the database is only mounted and not opened, which genrally means that data dictionary is not accessible. Empty blocks are blocks that don't have any rows in them but are allocated to an extent. New or unallocated blocks are blocks that have been initialized when the datafile was allocated to the tablespace but have not been assigned to any object (table, index, materialized view, cluster, partition or alike) -Original Message- Sent: Thursday, April 03, 2003 4:24 PM To: Multiple recipients of list ORACLE-L Actually this is how RMAN works. It writes all blocks up to the HWM of a given table, even empty ones. So, if your HWM is artifically high, you will encounter backups that are larger than they need to be. Oracle9i RMAN Backup and Recovery On bookshelves now! RF -Original Message- To: Multiple recipients of list ORACLE-L Sent: 4/3/2003 11:19 AM Keith Here is my understanding (don't rely on this one). When Oracle allocates tablespace, the disk blocks are cleared. My interpretation is that when RMAN encounters a clear block, it doesn't write it to the backup piece. I don't think it spends a lot of time trying to figure out above HWM and such. Dennis Williams DBA, 40%OCP, 100% DBA Lifetouch, Inc. [EMAIL PROTECTED] -Original Message- Sent: Thursday, April 03, 2003 10:44 AM To: Multiple recipients of list ORACLE-L Our RMAN backup is backing up much more than the actual data blocks when doing a full backup. I know that it backs up all blocks that have ever been used, but I'm trying to figure out exactly what that means. My first thought was that it backs up all blocks below the HWM, but I analyzed the tables and that is not the case. Sometimes it backs up more blocks than exist below the HWM for the tables and sometimes it backs up fewer blocks than those below the HWM. We are doing this to determine what we can do to reduce the size of the backup. Anyone have an idea how this works? Keith -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: DENNIS WILLIAMS INET: [EMAIL PROTECTED] Fat City Network Services-- 858-538-5051 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: [EMAIL PROTECTED] (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 -- Author: Freeman Robert - IL INET: [EMAIL PROTECTED] Fat City Network Services-- 858-538-5051 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: [EMAIL PROTECTED] (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:
RE: RMAN: What blocks are backed up with a full backup?
What it doesn't write are the blocks that are not allocated to any extent. RMAN doesn't go into the logical structures, like tables and indexes, it looks into the tablespace header and reads the information from the bitmap information there. It cannot go into tables/indexes because it should also work when the database is only mounted and not opened, which genrally means that data dictionary is not accessible. Empty blocks are blocks that don't have any rows in them but are allocated to an extent. New or unallocated blocks are blocks that have been initialized when the datafile was allocated to the tablespace but have not been assigned to any object (table, index, materialized view, cluster, partition or alike) -Original Message- Sent: Thursday, April 03, 2003 4:24 PM To: Multiple recipients of list ORACLE-L Actually this is how RMAN works. It writes all blocks up to the HWM of a given table, even empty ones. So, if your HWM is artifically high, you will encounter backups that are larger than they need to be. Oracle9i RMAN Backup and Recovery On bookshelves now! RF -Original Message- To: Multiple recipients of list ORACLE-L Sent: 4/3/2003 11:19 AM Keith Here is my understanding (don't rely on this one). When Oracle allocates tablespace, the disk blocks are cleared. My interpretation is that when RMAN encounters a clear block, it doesn't write it to the backup piece. I don't think it spends a lot of time trying to figure out above HWM and such. Dennis Williams DBA, 40%OCP, 100% DBA Lifetouch, Inc. [EMAIL PROTECTED] -Original Message- Sent: Thursday, April 03, 2003 10:44 AM To: Multiple recipients of list ORACLE-L Our RMAN backup is backing up much more than the actual data blocks when doing a full backup. I know that it backs up all blocks that have ever been used, but I'm trying to figure out exactly what that means. My first thought was that it backs up all blocks below the HWM, but I analyzed the tables and that is not the case. Sometimes it backs up more blocks than exist below the HWM for the tables and sometimes it backs up fewer blocks than those below the HWM. We are doing this to determine what we can do to reduce the size of the backup. Anyone have an idea how this works? Keith -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: DENNIS WILLIAMS INET: [EMAIL PROTECTED] Fat City Network Services-- 858-538-5051 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: [EMAIL PROTECTED] (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 -- Author: Freeman Robert - IL INET: [EMAIL PROTECTED] Fat City Network Services-- 858-538-5051 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: [EMAIL PROTECTED] (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 -- Author: Gogala, Mladen INET: [EMAIL PROTECTED] Fat City Network Services-- 858-538-5051 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: [EMAIL PROTECTED] (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).
RE: RMAN: What blocks are backed up with a full backup?
This is accurate and far more correct than my quickly written statement was. I actually say this almost word for word in the book. This is why even a table truncate will not reduce RMAN space usage. Sorry, I'll endevor in the future to be more susinct! :-) RF -Original Message- To: Multiple recipients of list ORACLE-L Sent: 4/4/2003 10:13 AM What it doesn't write are the blocks that are not allocated to any extent. RMAN doesn't go into the logical structures, like tables and indexes, it looks into the tablespace header and reads the information from the bitmap information there. It cannot go into tables/indexes because it should also work when the database is only mounted and not opened, which genrally means that data dictionary is not accessible. Empty blocks are blocks that don't have any rows in them but are allocated to an extent. New or unallocated blocks are blocks that have been initialized when the datafile was allocated to the tablespace but have not been assigned to any object (table, index, materialized view, cluster, partition or alike) -Original Message- Sent: Thursday, April 03, 2003 4:24 PM To: Multiple recipients of list ORACLE-L Actually this is how RMAN works. It writes all blocks up to the HWM of a given table, even empty ones. So, if your HWM is artifically high, you will encounter backups that are larger than they need to be. Oracle9i RMAN Backup and Recovery On bookshelves now! RF -Original Message- To: Multiple recipients of list ORACLE-L Sent: 4/3/2003 11:19 AM Keith Here is my understanding (don't rely on this one). When Oracle allocates tablespace, the disk blocks are cleared. My interpretation is that when RMAN encounters a clear block, it doesn't write it to the backup piece. I don't think it spends a lot of time trying to figure out above HWM and such. Dennis Williams DBA, 40%OCP, 100% DBA Lifetouch, Inc. [EMAIL PROTECTED] -Original Message- Sent: Thursday, April 03, 2003 10:44 AM To: Multiple recipients of list ORACLE-L Our RMAN backup is backing up much more than the actual data blocks when doing a full backup. I know that it backs up all blocks that have ever been used, but I'm trying to figure out exactly what that means. My first thought was that it backs up all blocks below the HWM, but I analyzed the tables and that is not the case. Sometimes it backs up more blocks than exist below the HWM for the tables and sometimes it backs up fewer blocks than those below the HWM. We are doing this to determine what we can do to reduce the size of the backup. Anyone have an idea how this works? Keith -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: DENNIS WILLIAMS INET: [EMAIL PROTECTED] Fat City Network Services-- 858-538-5051 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: [EMAIL PROTECTED] (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 -- Author: Freeman Robert - IL INET: [EMAIL PROTECTED] Fat City Network Services-- 858-538-5051 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: [EMAIL PROTECTED] (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 -- Author: Gogala, Mladen INET: [EMAIL PROTECTED] Fat City Network Services-- 858-538-5051 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: [EMAIL PROTECTED] (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 -- Author: Freeman Robert - IL INET: [EMAIL PROTECTED] Fat City Network Services-- 858-538-5051 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
Re: RMAN: What blocks are backed up with a full backup?
This matches the data I have collected, with the following addition: RMAN will backup any blocks that have ever had data in them, even if the extent has been deallocated or the object dropped. Keith - Original Message - To: Multiple recipients of list ORACLE-L [EMAIL PROTECTED] Sent: Friday, April 04, 2003 10:13 AM What it doesn't write are the blocks that are not allocated to any extent. RMAN doesn't go into the logical structures, like tables and indexes, it looks into the tablespace header and reads the information from the bitmap information there. It cannot go into tables/indexes because it should also work when the database is only mounted and not opened, which genrally means that data dictionary is not accessible. Empty blocks are blocks that don't have any rows in them but are allocated to an extent. New or unallocated blocks are blocks that have been initialized when the datafile was allocated to the tablespace but have not been assigned to any object (table, index, materialized view, cluster, partition or alike) -Original Message- Sent: Thursday, April 03, 2003 4:24 PM To: Multiple recipients of list ORACLE-L Actually this is how RMAN works. It writes all blocks up to the HWM of a given table, even empty ones. So, if your HWM is artifically high, you will encounter backups that are larger than they need to be. Oracle9i RMAN Backup and Recovery On bookshelves now! RF -Original Message- To: Multiple recipients of list ORACLE-L Sent: 4/3/2003 11:19 AM Keith Here is my understanding (don't rely on this one). When Oracle allocates tablespace, the disk blocks are cleared. My interpretation is that when RMAN encounters a clear block, it doesn't write it to the backup piece. I don't think it spends a lot of time trying to figure out above HWM and such. Dennis Williams DBA, 40%OCP, 100% DBA Lifetouch, Inc. [EMAIL PROTECTED] -Original Message- Sent: Thursday, April 03, 2003 10:44 AM To: Multiple recipients of list ORACLE-L Our RMAN backup is backing up much more than the actual data blocks when doing a full backup. I know that it backs up all blocks that have ever been used, but I'm trying to figure out exactly what that means. My first thought was that it backs up all blocks below the HWM, but I analyzed the tables and that is not the case. Sometimes it backs up more blocks than exist below the HWM for the tables and sometimes it backs up fewer blocks than those below the HWM. We are doing this to determine what we can do to reduce the size of the backup. Anyone have an idea how this works? Keith -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: DENNIS WILLIAMS INET: [EMAIL PROTECTED] Fat City Network Services-- 858-538-5051 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: [EMAIL PROTECTED] (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 -- Author: Freeman Robert - IL INET: [EMAIL PROTECTED] Fat City Network Services-- 858-538-5051 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: [EMAIL PROTECTED] (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 -- Author: Gogala, Mladen INET: [EMAIL PROTECTED] Fat City Network Services-- 858-538-5051 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: [EMAIL PROTECTED] (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). The information transmitted is intended only for the person or entity to which it is addressed and may contain confidential and/or privileged material. If the reader of this message is not the intended recipient, you are hereby notified that your access is unauthorized, and any review, dissemination, distribution or copying of this
RE: RMAN: What blocks are backed up with a full backup?
I apologize, I shouldn't be trying to teach the master. -Original Message- Sent: Friday, April 04, 2003 12:09 PM To: Multiple recipients of list ORACLE-L This is accurate and far more correct than my quickly written statement was. I actually say this almost word for word in the book. This is why even a table truncate will not reduce RMAN space usage. Sorry, I'll endevor in the future to be more susinct! :-) RF -Original Message- To: Multiple recipients of list ORACLE-L Sent: 4/4/2003 10:13 AM What it doesn't write are the blocks that are not allocated to any extent. RMAN doesn't go into the logical structures, like tables and indexes, it looks into the tablespace header and reads the information from the bitmap information there. It cannot go into tables/indexes because it should also work when the database is only mounted and not opened, which genrally means that data dictionary is not accessible. Empty blocks are blocks that don't have any rows in them but are allocated to an extent. New or unallocated blocks are blocks that have been initialized when the datafile was allocated to the tablespace but have not been assigned to any object (table, index, materialized view, cluster, partition or alike) -Original Message- Sent: Thursday, April 03, 2003 4:24 PM To: Multiple recipients of list ORACLE-L Actually this is how RMAN works. It writes all blocks up to the HWM of a given table, even empty ones. So, if your HWM is artifically high, you will encounter backups that are larger than they need to be. Oracle9i RMAN Backup and Recovery On bookshelves now! RF -Original Message- To: Multiple recipients of list ORACLE-L Sent: 4/3/2003 11:19 AM Keith Here is my understanding (don't rely on this one). When Oracle allocates tablespace, the disk blocks are cleared. My interpretation is that when RMAN encounters a clear block, it doesn't write it to the backup piece. I don't think it spends a lot of time trying to figure out above HWM and such. Dennis Williams DBA, 40%OCP, 100% DBA Lifetouch, Inc. [EMAIL PROTECTED] -Original Message- Sent: Thursday, April 03, 2003 10:44 AM To: Multiple recipients of list ORACLE-L Our RMAN backup is backing up much more than the actual data blocks when doing a full backup. I know that it backs up all blocks that have ever been used, but I'm trying to figure out exactly what that means. My first thought was that it backs up all blocks below the HWM, but I analyzed the tables and that is not the case. Sometimes it backs up more blocks than exist below the HWM for the tables and sometimes it backs up fewer blocks than those below the HWM. We are doing this to determine what we can do to reduce the size of the backup. Anyone have an idea how this works? Keith -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: DENNIS WILLIAMS INET: [EMAIL PROTECTED] Fat City Network Services-- 858-538-5051 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: [EMAIL PROTECTED] (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 -- Author: Freeman Robert - IL INET: [EMAIL PROTECTED] Fat City Network Services-- 858-538-5051 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: [EMAIL PROTECTED] (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 -- Author: Gogala, Mladen INET: [EMAIL PROTECTED] Fat City Network Services-- 858-538-5051 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: [EMAIL PROTECTED] (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 -- Author: Freeman Robert - IL INET: [EMAIL PROTECTED] Fat City Network Services-- 858-538-5051 http://www.fatcity.com San Diego, California-- Mailing
RE: RMAN: What blocks are backed up with a full backup?
Teach me? Hell, there is more stuff in the world I don't know than I know of! I've been wrong before and I'll be wrong again and and I hate this, I FORGET STUFF. Easy stuff, simple stuff stuff I kick myself all over creation because I forgot it. Me the master, na Thats where Jonathan and Connor and others come in. Me, I'm a humble DBA who just wants to have some fun and answer an occational question correctly. RF -Original Message- To: Multiple recipients of list ORACLE-L Sent: 4/4/2003 12:03 PM I apologize, I shouldn't be trying to teach the master. -Original Message- Sent: Friday, April 04, 2003 12:09 PM To: Multiple recipients of list ORACLE-L This is accurate and far more correct than my quickly written statement was. I actually say this almost word for word in the book. This is why even a table truncate will not reduce RMAN space usage. Sorry, I'll endevor in the future to be more susinct! :-) RF -Original Message- To: Multiple recipients of list ORACLE-L Sent: 4/4/2003 10:13 AM What it doesn't write are the blocks that are not allocated to any extent. RMAN doesn't go into the logical structures, like tables and indexes, it looks into the tablespace header and reads the information from the bitmap information there. It cannot go into tables/indexes because it should also work when the database is only mounted and not opened, which genrally means that data dictionary is not accessible. Empty blocks are blocks that don't have any rows in them but are allocated to an extent. New or unallocated blocks are blocks that have been initialized when the datafile was allocated to the tablespace but have not been assigned to any object (table, index, materialized view, cluster, partition or alike) -Original Message- Sent: Thursday, April 03, 2003 4:24 PM To: Multiple recipients of list ORACLE-L Actually this is how RMAN works. It writes all blocks up to the HWM of a given table, even empty ones. So, if your HWM is artifically high, you will encounter backups that are larger than they need to be. Oracle9i RMAN Backup and Recovery On bookshelves now! RF -Original Message- To: Multiple recipients of list ORACLE-L Sent: 4/3/2003 11:19 AM Keith Here is my understanding (don't rely on this one). When Oracle allocates tablespace, the disk blocks are cleared. My interpretation is that when RMAN encounters a clear block, it doesn't write it to the backup piece. I don't think it spends a lot of time trying to figure out above HWM and such. Dennis Williams DBA, 40%OCP, 100% DBA Lifetouch, Inc. [EMAIL PROTECTED] -Original Message- Sent: Thursday, April 03, 2003 10:44 AM To: Multiple recipients of list ORACLE-L Our RMAN backup is backing up much more than the actual data blocks when doing a full backup. I know that it backs up all blocks that have ever been used, but I'm trying to figure out exactly what that means. My first thought was that it backs up all blocks below the HWM, but I analyzed the tables and that is not the case. Sometimes it backs up more blocks than exist below the HWM for the tables and sometimes it backs up fewer blocks than those below the HWM. We are doing this to determine what we can do to reduce the size of the backup. Anyone have an idea how this works? Keith -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: DENNIS WILLIAMS INET: [EMAIL PROTECTED] Fat City Network Services-- 858-538-5051 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: [EMAIL PROTECTED] (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 -- Author: Freeman Robert - IL INET: [EMAIL PROTECTED] Fat City Network Services-- 858-538-5051 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: [EMAIL PROTECTED] (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 -- Author: Gogala, Mladen INET: [EMAIL PROTECTED] Fat City Network Services-- 858-538-5051 http://www.fatcity.com San Diego, California-- Mailing list and web hosting services - To REMOVE yourself from this
Re: RMAN: What blocks are backed up with a full backup?
[EMAIL PROTECTED] wrote: Teach me? Hell, there is more stuff in the world I don't know than I know of! I've been wrong before and I'll be wrong again and and I hate this, I FORGET STUFF. Easy stuff, simple stuff stuff I kick myself all over creation because I forgot it. yup, simple stuff you do without thinking about, then you can't remember shit when someone asks you about it.;-) i think it's called getting old.;-) -- -- Bill Shrek Thater ORACLE DBA [EMAIL PROTECTED] Om mani padme hum. -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: bill thater INET: [EMAIL PROTECTED] Fat City Network Services-- 858-538-5051 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: [EMAIL PROTECTED] (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).
RE: RMAN: What blocks are backed up with a full backup?
...getting old... Noo RF -Original Message- To: Multiple recipients of list ORACLE-L Sent: 4/4/2003 3:48 PM [EMAIL PROTECTED] wrote: Teach me? Hell, there is more stuff in the world I don't know than I know of! I've been wrong before and I'll be wrong again and and I hate this, I FORGET STUFF. Easy stuff, simple stuff stuff I kick myself all over creation because I forgot it. yup, simple stuff you do without thinking about, then you can't remember shit when someone asks you about it.;-) i think it's called getting old.;-) -- -- Bill Shrek Thater ORACLE DBA [EMAIL PROTECTED] Om mani padme hum. -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: bill thater INET: [EMAIL PROTECTED] Fat City Network Services-- 858-538-5051 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: [EMAIL PROTECTED] (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 -- Author: Freeman Robert - IL INET: [EMAIL PROTECTED] Fat City Network Services-- 858-538-5051 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: [EMAIL PROTECTED] (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).
RE: RMAN: What blocks are backed up with a full backup?
Keith Here is my understanding (don't rely on this one). When Oracle allocates tablespace, the disk blocks are cleared. My interpretation is that when RMAN encounters a clear block, it doesn't write it to the backup piece. I don't think it spends a lot of time trying to figure out above HWM and such. Dennis Williams DBA, 40%OCP, 100% DBA Lifetouch, Inc. [EMAIL PROTECTED] -Original Message- Sent: Thursday, April 03, 2003 10:44 AM To: Multiple recipients of list ORACLE-L Our RMAN backup is backing up much more than the actual data blocks when doing a full backup. I know that it backs up all blocks that have ever been used, but I'm trying to figure out exactly what that means. My first thought was that it backs up all blocks below the HWM, but I analyzed the tables and that is not the case. Sometimes it backs up more blocks than exist below the HWM for the tables and sometimes it backs up fewer blocks than those below the HWM. We are doing this to determine what we can do to reduce the size of the backup. Anyone have an idea how this works? Keith -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: DENNIS WILLIAMS INET: [EMAIL PROTECTED] Fat City Network Services-- 858-538-5051 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: [EMAIL PROTECTED] (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).
RE: RMAN: What blocks are backed up with a full backup?
Actually this is how RMAN works. It writes all blocks up to the HWM of a given table, even empty ones. So, if your HWM is artifically high, you will encounter backups that are larger than they need to be. Oracle9i RMAN Backup and Recovery On bookshelves now! RF -Original Message- To: Multiple recipients of list ORACLE-L Sent: 4/3/2003 11:19 AM Keith Here is my understanding (don't rely on this one). When Oracle allocates tablespace, the disk blocks are cleared. My interpretation is that when RMAN encounters a clear block, it doesn't write it to the backup piece. I don't think it spends a lot of time trying to figure out above HWM and such. Dennis Williams DBA, 40%OCP, 100% DBA Lifetouch, Inc. [EMAIL PROTECTED] -Original Message- Sent: Thursday, April 03, 2003 10:44 AM To: Multiple recipients of list ORACLE-L Our RMAN backup is backing up much more than the actual data blocks when doing a full backup. I know that it backs up all blocks that have ever been used, but I'm trying to figure out exactly what that means. My first thought was that it backs up all blocks below the HWM, but I analyzed the tables and that is not the case. Sometimes it backs up more blocks than exist below the HWM for the tables and sometimes it backs up fewer blocks than those below the HWM. We are doing this to determine what we can do to reduce the size of the backup. Anyone have an idea how this works? Keith -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: DENNIS WILLIAMS INET: [EMAIL PROTECTED] Fat City Network Services-- 858-538-5051 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: [EMAIL PROTECTED] (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 -- Author: Freeman Robert - IL INET: [EMAIL PROTECTED] Fat City Network Services-- 858-538-5051 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: [EMAIL PROTECTED] (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).
RE: RMAN: What blocks are backed up with a full backup?
Keith Like I said, don't rely on my interpretation. Believe Robert -- he wrote the book! And yes, buy the book. Great book, highly recommended. http://www.amazon.com/exec/obidos/tg/detail/-/0072226625/qid=1049405966/sr=8 -1/ref=sr_8_1/002-7783294-4962413?v=glances=booksn=507846 Dennis Williams DBA, 40%OCP, 100% DBA Lifetouch, Inc. [EMAIL PROTECTED] -Original Message- Sent: Thursday, April 03, 2003 3:26 PM To: DENNIS WILLIAMS; 'Multiple recipients of list ORACLE-L ' Actually this is how RMAN works. It writes all blocks up to the HWM of a given table, even empty ones. So, if your HWM is artifically high, you will encounter backups that are larger than they need to be. Oracle9i RMAN Backup and Recovery On bookshelves now! RF -Original Message- To: Multiple recipients of list ORACLE-L Sent: 4/3/2003 11:19 AM Keith Here is my understanding (don't rely on this one). When Oracle allocates tablespace, the disk blocks are cleared. My interpretation is that when RMAN encounters a clear block, it doesn't write it to the backup piece. I don't think it spends a lot of time trying to figure out above HWM and such. Dennis Williams DBA, 40%OCP, 100% DBA Lifetouch, Inc. [EMAIL PROTECTED] -Original Message- Sent: Thursday, April 03, 2003 10:44 AM To: Multiple recipients of list ORACLE-L Our RMAN backup is backing up much more than the actual data blocks when doing a full backup. I know that it backs up all blocks that have ever been used, but I'm trying to figure out exactly what that means. My first thought was that it backs up all blocks below the HWM, but I analyzed the tables and that is not the case. Sometimes it backs up more blocks than exist below the HWM for the tables and sometimes it backs up fewer blocks than those below the HWM. We are doing this to determine what we can do to reduce the size of the backup. Anyone have an idea how this works? Keith -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: DENNIS WILLIAMS INET: [EMAIL PROTECTED] Fat City Network Services-- 858-538-5051 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: [EMAIL PROTECTED] (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 -- Author: DENNIS WILLIAMS INET: [EMAIL PROTECTED] Fat City Network Services-- 858-538-5051 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: [EMAIL PROTECTED] (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).
Re: RMAN: What blocks are backed up with a full backup?
I should have stated that this is Oracle 8.0.5, if that makes a difference. After posting the questions, I went to Metalink and found some conflicting informaiton, but the consensus seemed to be that it was unrelated to the HWM of the tables. For example, after dropping a table, all the blocks were still being backed up. And as I said, for some tablespaces, it backs up many more blocks than are below the HWM blocks of the tables and in other cases it backs up fewer blocks than those below the HWM. My current thinking is that the best way to reduce the backup size is to resize the datafiles as small as possible and then resize them back to the original size. This should reduce the size some, but I don't think there is any way to tell how much. To get the maximum reduction, we could export...receate tablespaces...import, but it's not worth that much effort. Keith - Original Message - To: Multiple recipients of list ORACLE-L [EMAIL PROTECTED] Sent: Thursday, April 03, 2003 3:23 PM Actually this is how RMAN works. It writes all blocks up to the HWM of a given table, even empty ones. So, if your HWM is artifically high, you will encounter backups that are larger than they need to be. Oracle9i RMAN Backup and Recovery On bookshelves now! RF -Original Message- To: Multiple recipients of list ORACLE-L Sent: 4/3/2003 11:19 AM Keith Here is my understanding (don't rely on this one). When Oracle allocates tablespace, the disk blocks are cleared. My interpretation is that when RMAN encounters a clear block, it doesn't write it to the backup piece. I don't think it spends a lot of time trying to figure out above HWM and such. Dennis Williams DBA, 40%OCP, 100% DBA Lifetouch, Inc. [EMAIL PROTECTED] -Original Message- Sent: Thursday, April 03, 2003 10:44 AM To: Multiple recipients of list ORACLE-L Our RMAN backup is backing up much more than the actual data blocks when doing a full backup. I know that it backs up all blocks that have ever been used, but I'm trying to figure out exactly what that means. My first thought was that it backs up all blocks below the HWM, but I analyzed the tables and that is not the case. Sometimes it backs up more blocks than exist below the HWM for the tables and sometimes it backs up fewer blocks than those below the HWM. We are doing this to determine what we can do to reduce the size of the backup. Anyone have an idea how this works? Keith -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: DENNIS WILLIAMS INET: [EMAIL PROTECTED] Fat City Network Services-- 858-538-5051 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: [EMAIL PROTECTED] (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 -- Author: Freeman Robert - IL INET: [EMAIL PROTECTED] Fat City Network Services-- 858-538-5051 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: [EMAIL PROTECTED] (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 -- Author: Keith Moore INET: [EMAIL PROTECTED] Fat City Network Services-- 858-538-5051 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: [EMAIL PROTECTED] (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).
