okay, if I hadn't already been convinced not to use it, this would clinch it... we will have joins of 16+ tables to one of the fact tables and I can't impede performance. This is a very visible system and needs to be as good as it can be
--- Connor McDonald <[EMAIL PROTECTED]> wrote: > You need to benchmark ASSM carefully because it may > have impact especially on your smaller tables. To > avoid the concurrency issues, you can end up with > blocks "sprayed" as rows are created. For example, > you might add a single row to an (empty) table and end > up with the table being 10 blocks instead of 1 because > ASSM tries to spread blocks around in this fashion. > > If those tables are targets of joins ( to large > tables) as they often tend to be in DW, you might be > trawling through a much larger amount of blocks then > you need to be... > > hth > connor > > --- Rachel Carmichael <[EMAIL PROTECTED]> wrote: > > Thanks Ian, that was indeed the question, although > > the other > > information is useful as well. > > > > if I understand what you are saying correctly, it > > works but it won't > > really buy me anything and I might do better > > controlling the space > > myself. And while you have had no problems, you've > > heard negative > > things about it. I can't afford to have this > > database not be available > > so I'll manage them on my own > > > > Rachel > > > > --- "MacGregor, Ian A." <[EMAIL PROTECTED]> > > wrote: > > > The question posed was not whether "extent > > management local" should > > > be used, but whether automatic segment space > > management should be > > > used. > > > > > > As this is a data warehouse, I would not expect > > you to have > > > transactions trying to change the same block. > > Assuming you are > > > loading; that is, inserting data and not doing > > updates, wouldn't you > > > try to cram as much data as possible into a block? > > Seems this could > > > be done more easily by controlling these > > parameters yourself > > > > > > I've got one system using automatic segment space > > management without > > > any problems, however when I posed the same > > question on using it a > > > few months ago, the respone which trickled in way > > highly negative > > > concerning its usage. > > > > > > Ian MacGregor > > > Stanford Linear Accelerator Center > > > [EMAIL PROTECTED] > > > > > > -----Original Message----- > > > Sent: Tuesday, September 03, 2002 8:49 AM > > > To: Multiple recipients of list ORACLE-L > > > > > > > > > time for me to ask the experts again. > > > > > > My data warehouse will be 9.2, with all locally > > managed tablespaces. > > > We > > > will be following what I have taken to calling the > > "Goldilocks" > > > principle -- that of small, medium and large > > tablespace extent sizes, > > > with variations in that we will separate indexes > > and data, and will > > > have even more separation for our fact tables into > > partitioned tables > > > and tablespaces. > > > > > > However, now comes the time for me to work out > > storage clauses. And a > > > quick read through the docs leaves me wondering if > > I should just turn > > > on automatic segment-space management and not > > worry about setting > > > PCTFREE, PCTUSED and FREELIST parameters. I can't > > find any real > > > information or bugs on MetaLink either. > > > > > > Does anyone have any experience, good OR bad, with > > using this > > > feature? > > > If you are doing data warehouse work, what are > > good values for the > > > parameters if I DO use them? One fact table is > > likely to be highly > > > updated (customer info) as we collect more and > > more specific > > > information from customers. The rest will be, as > > you would expect > > > from > > > a DW, mostly inserts. > > > > > > Help? > > > > > > Thanks! > > > > > > Rachel > > > > > > __________________________________________________ > > > Do You Yahoo!? > > > Yahoo! Finance - Get real-time stock quotes > > > http://finance.yahoo.com > > > -- > > > Please see the official ORACLE-L FAQ: > > http://www.orafaq.com > > > -- > > > Author: Rachel Carmichael > > > 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: MacGregor, Ian A. > > > 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). > > > > > > __________________________________________________ > > Do You Yahoo!? > > Yahoo! Finance - Get real-time stock quotes > > http://finance.yahoo.com > > -- > > Please see the official ORACLE-L FAQ: > > http://www.orafaq.com > > -- > > Author: Rachel Carmichael > > 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). > > ===== > Connor McDonald > http://www.oracledba.co.uk > === message truncated === __________________________________________________ Do You Yahoo!? Yahoo! Finance - Get real-time stock quotes http://finance.yahoo.com -- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: Rachel Carmichael 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).
