Re: Should each partition have it's own tablespace and datafile?
One tablespace per partition. If you're not sure of the final size of the partition, consider putting each tablespace file with autoexend ON and specify max filesize (MAXSIZE). For example: if partition extent size is 10M, the autoextend value could be 100M to have room for 10 more extents. This tip helps avoid a lot of wasted space AND/OR getting calls in the middle of the night to make the filesize larger. Be sure the autoextend does not attempt to extend the filesize beyond the capacity of the disk. Sizes chosen would depend upon your knowledge of the partition size needed to hold the data and your strategy. Could also autoextend at 10M, but performance would be affected if a lot of new extents were added during a load. Syntax: CREATE TABLESPACE CUST_DATA_0401 DATAFILE '/u5/oracle/oradata/data/cust_data_0401.dbf' SIZE 100M AUTOEXTEND ON NEXT 100M MAXSIZE 500M; and the corresponding index - file size dependent upon how many indexes present on the table and how large the column sizes are. If you have five indexes (in a datawarehousing environment), the size of the index tablespace COULD be larger than the corresponding data tablespace. CREATE TABLESPACE CUST_IDX_0401 DATAFILE '/u06/oracle/oradata/index/cust_idx_0401.dbf' SIZE 50M AUTOEXTEND ON NEXT 10M MAXSIZE 300M; Jenny Jacobson Oracle DBA Consultant Member - RMP Consulting Partners LLC - Member NAACB Available for project On Wed, 11 Apr 2001 [EMAIL PROTECTED] wrote: We have a 120 Gig datawarehouse that uses more than 100 date-based partitions. For financial and political reasons, we have run out of disk space to give this database as it continues in it's relentless growth. The developers have resigned themselves to purge out some of the old data and get rid of partitions that are more than two years old. We currently have about ten tablespaces that contain all of the data and indexes for this database. There is a small, medium, and large tablespace for data and for indexes plus some other specialized tablespaces by functionality. Anyway, dropping a couple dozen of these partitions is not going to be enough to free up some disk space for us. Instead we're going to have to export our data, drop the tablespaces, and recreate them as a smaller size and then reimport the data minus the dropped partitions. Since we're going to all of this work, I'm wondering if we should reorg these partitions by creating a tablespace for each partition and a single datafile for each tablespace. That way in the future, every time we want to drop a partition, it will be very easy to reclaim the disk space associated with that partition. I don't want to have to do these reorgs every month. How do most places physically lay out their partitions? What is the downside of having a datafile for each partition? Wasted space? Would a compromise be to assign six months worth of partitions to a single tablespace? We are currently on version 8.0.4 of Oracle on Sun Solaris 2.6 but we will be upgrading soon to 8.1.7. Looks like I may need to reorg this before we can upgrade as we are rapidly running out of room. Thanks, Cherie Machler Gelco Information Network -- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: INET: [EMAIL PROTECTED] 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 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.com -- Author: Jenny Jacobson INET: [EMAIL PROTECTED] 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 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: Should each partition have it's own tablespace and datafile?
Hi Cherie, I am in favor of one tablespace per partition. For availablity and maintenance purposes it certainly helps us in our environment. I have implemented this concept in our data mart database which is is now around 90GB. There are multiple datafiles per tablepace each representing an extent (~500 MB). We load data to this database once a month, so I am not too concerned with the checkpoint times etc. (due to a number of data files). There are 4 large tables with 10 partitions so far (one per year). Each table has 2-3 indexes, all locally partitioned. Again each in its own tablespace. Partitioning key is the 4 digit year. All tablespaces and partition names contain the 2 digit year for ease of understanding what's in them. Partitioned table data and partitioned index data is placed on physically separate storage devices. Since, all the data comes from other legacy (or otherwise, internal) systems, we do not have a partition for 'MAXVALUE', and that saves me a lot of work when adding new partitions for new years (did that for 2000 and 2001). Working very well for the last 2 years now, started out with 8.0 and recently upgraded to 8.1.7. All this was done as a parallel process and soon (next month) it will all be 'real' production with one more set of storage devices to split data and index further. HTH.. - Kirti Deshpande Verizon Information Services http://www.superpages.com -Original Message- From: [EMAIL PROTECTED] [SMTP:[EMAIL PROTECTED]] Sent: Wednesday, April 11, 2001 2:06 PM To: Multiple recipients of list ORACLE-L Subject: Should each partition have it's own tablespace and datafile? We have a 120 Gig datawarehouse that uses more than 100 date-based partitions. For financial and political reasons, we have run out of disk space to give this database as it continues in it's relentless growth. The developers have resigned themselves to purge out some of the old data and get rid of partitions that are more than two years old. We currently have about ten tablespaces that contain all of the data and indexes for this database. There is a small, medium, and large tablespace for data and for indexes plus some other specialized tablespaces by functionality. Anyway, dropping a couple dozen of these partitions is not going to be enough to free up some disk space for us. Instead we're going to have to export our data, drop the tablespaces, and recreate them as a smaller size and then reimport the data minus the dropped partitions. Since we're going to all of this work, I'm wondering if we should reorg these partitions by creating a tablespace for each partition and a single datafile for each tablespace. That way in the future, every time we want to drop a partition, it will be very easy to reclaim the disk space associated with that partition. I don't want to have to do these reorgs every month. How do most places physically lay out their partitions? What is the downside of having a datafile for each partition? Wasted space? Would a compromise be to assign six months worth of partitions to a single tablespace? We are currently on version 8.0.4 of Oracle on Sun Solaris 2.6 but we will be upgrading soon to 8.1.7. Looks like I may need to reorg this before we can upgrade as we are rapidly running out of room. Thanks, Cherie Machler Gelco Information Network -- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: INET: [EMAIL PROTECTED] 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 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.com -- Author: Deshpande, Kirti INET: [EMAIL PROTECTED] 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 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: Should each partition have it's own tablespace and datafile?
In my experience, a separate tablespace per partition is advisable; you don't get the full benefit of partition management options otherwise. - Original Message - To: "Multiple recipients of list ORACLE-L" [EMAIL PROTECTED] Sent: Wednesday, April 11, 2001 3:05 PM We have a 120 Gig datawarehouse that uses more than 100 date-based partitions. For financial and political reasons, we have run out of disk space to give this database as it continues in it's relentless growth. The developers have resigned themselves to purge out some of the old data and get rid of partitions that are more than two years old. We currently have about ten tablespaces that contain all of the data and indexes for this database. There is a small, medium, and large tablespace for data and for indexes plus some other specialized tablespaces by functionality. Anyway, dropping a couple dozen of these partitions is not going to be enough to free up some disk space for us. Instead we're going to have to export our data, drop the tablespaces, and recreate them as a smaller size and then reimport the data minus the dropped partitions. Since we're going to all of this work, I'm wondering if we should reorg these partitions by creating a tablespace for each partition and a single datafile for each tablespace. That way in the future, every time we want to drop a partition, it will be very easy to reclaim the disk space associated with that partition. I don't want to have to do these reorgs every month. How do most places physically lay out their partitions? What is the downside of having a datafile for each partition? Wasted space? Would a compromise be to assign six months worth of partitions to a single tablespace? We are currently on version 8.0.4 of Oracle on Sun Solaris 2.6 but we will be upgrading soon to 8.1.7. Looks like I may need to reorg this before we can upgrade as we are rapidly running out of room. Thanks, Cherie Machler Gelco Information Network -- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: INET: [EMAIL PROTECTED] 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 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.com -- Author: Paul Baumgartel INET: [EMAIL PROTECTED] 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 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).