RE: LOB Storage
Tanel Kevin, Thanks for the replies. Very helpful. I am using version 9.2.0.3. You both confirmed what I thought I should do. thanks again. Tom Mercadante Oracle Certified Professional -Original Message- Sent: Tuesday, September 30, 2003 5:04 PM To: Multiple recipients of list ORACLE-L Hi! On which version you are? I would create fairly large extents, 64MB for example. LOBs are stored in chunks anyway, extent size doesn't matter that much. One issue is, if you create very large extent size, you might waste some space in LOB index which is a separate, smaller segment (but is always stored with LOB data segment in 9i). But your LOBs will work with 64k extent sizes as well, but that way you might lose some benefit on multiblock direct reads. Btw, if you use enable storage in row then LOB index entries are always stored in row, which means for smaller LOBs which don't fit inline, no LOB index lookup is needed (for large ones I believe there still is, because large LOBs can't be addressed with small inline inode structure). If your average lob size is in megabytes, I'd put them into 16k or 32k tablespaces, away from regular block size and create a different buffer pool for them - if you are using CACHE type lobs. That way they won't affect LRU mechanisms for normal data buffers. Tanel. - Original Message - To: Multiple recipients of list ORACLE-L [EMAIL PROTECTED] Sent: Tuesday, September 30, 2003 11:24 PM All, I'm being given a requirement to store a BLOB column in the database. I'm being told that the average size of the file (it's a PDF) is 12,000 K. I'm assuming that I should store this column in a separate tablespace from the table data. If I use an LMT tablespace, what should I use for the uniform allocation size? Should I use 12,000 K or something larger to store one PDF per segment? Am I all wrong here? thanks in advance Tom Mercadante Oracle Certified Professional -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Mercadante, Thomas F 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: Tanel Poder 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: Mercadante, Thomas F 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: LOB Storage
Hi! On which version you are? I would create fairly large extents, 64MB for example. LOBs are stored in chunks anyway, extent size doesn't matter that much. One issue is, if you create very large extent size, you might waste some space in LOB index which is a separate, smaller segment (but is always stored with LOB data segment in 9i). But your LOBs will work with 64k extent sizes as well, but that way you might lose some benefit on multiblock direct reads. Btw, if you use enable storage in row then LOB index entries are always stored in row, which means for smaller LOBs which don't fit inline, no LOB index lookup is needed (for large ones I believe there still is, because large LOBs can't be addressed with small inline inode structure). If your average lob size is in megabytes, I'd put them into 16k or 32k tablespaces, away from regular block size and create a different buffer pool for them - if you are using CACHE type lobs. That way they won't affect LRU mechanisms for normal data buffers. Tanel. - Original Message - To: Multiple recipients of list ORACLE-L [EMAIL PROTECTED] Sent: Tuesday, September 30, 2003 11:24 PM All, I'm being given a requirement to store a BLOB column in the database. I'm being told that the average size of the file (it's a PDF) is 12,000 K. I'm assuming that I should store this column in a separate tablespace from the table data. If I use an LMT tablespace, what should I use for the uniform allocation size? Should I use 12,000 K or something larger to store one PDF per segment? Am I all wrong here? thanks in advance Tom Mercadante Oracle Certified Professional -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Mercadante, Thomas F 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: Tanel Poder 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: LOB Storage
Tom In this case, I would use a uniform extent size -- you know approximately how large the data is today. Since there is no measureable overhead for having multiple segments, I would go with something much smaller than a 12MB extent size -- 512K to 1MB, depending on what your OS read size is. Kevin Just Plain Certifiable -Original Message- Sent: Tuesday, September 30, 2003 4:25 PM To: Multiple recipients of list ORACLE-L All, I'm being given a requirement to store a BLOB column in the database. I'm being told that the average size of the file (it's a PDF) is 12,000 K. I'm assuming that I should store this column in a separate tablespace from the table data. If I use an LMT tablespace, what should I use for the uniform allocation size? Should I use 12,000 K or something larger to store one PDF per segment? Am I all wrong here? thanks in advance Tom Mercadante Oracle Certified Professional -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Mercadante, Thomas F 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: Kevin Toepke 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: LOB Storage Characteristics
uh - Stripe And Mirror Everything. what's a tablespace? add more NVRAM (cache). he he he he ... its going to be another late one ... sales critter. -Original Message- Sent: Monday, June 11, 2001 9:51 PM To: Multiple recipients of list ORACLE-L Greetings All, I am using Oracle 81630 on Solaris 7 and I have a table which contains a LOB (CLOB actually). The DDL statement is as follows ... My question is one related to data access for the table, lobsegment and lobindex. Would there be any I/O performance benefit in having the table, lobsegment and lobindex located in different tablespaces (which would be located on different physical drives)? As you can see I can split the table and lobsegment/lobindex into separate tablespaces. I have tried to split the lobsegment and lobindex up into separate tablespaces but according to the 816 documentation this is no longer supported under 8i (depracation of the LOB_index_clause). According to Metalink the lobsegment and lobindex are co-located in 8i for a specific reason - but I cannot find what that is! Thanks Glen -- Glen Mitchell NZ Phone: +64 9 3730400 Energy Research Lab URL: http://www.peace.com http://www.peace.com Peace Software Email: [EMAIL PROTECTED] -- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: Paul Drake 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).
