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Home -> Community -> Usenet -> c.d.o.misc -> Re: Big usr1xxx.ora Files ??
A copy of this was sent to "Markus Schwitter (Bitec)" <MrMagoo_at_plaza.ch>
(if that email address didn't require changing)
On Mon, 30 Nov 1998 19:29:01 +0100, you wrote:
>>Likewise, when you export, free space on blocks (pctfree settings) are not
>>'exported' -- an export file is dense where as table data might (by design)
>have
>>holes.
>
>So, what pctfree is a usually used parameter ? 10 ? or more ? Our DB is
>all-set, there will be no modification in the next year (touch wood)...
>Is there a tool, wich shows the exactly usage ? ..and an optimization tool
>to correct this ?
pctfree is defaulted to 10% meaning that 10% of any given block will be reserved from being used by an INSERT operation (90% of the blockspace may be used by an insert, after that, no new rows will be inserted in that block). the saved space is used by UPDATES that make the row grow bigger.
10% is the rule of thumb. If you only INSERT and never update, pctfree of 0 is ok.
if you want to use a different pctfree on a table -- you must rebuild the table. You can alter the table to change the pctfree for subsequent blocks but only rebuilding the table will 'compact' existing blocks.
[snip]
>
>Thanks, anyway, for the info !
>
>Markus
>
>
Thomas Kyte
tkyte_at_us.oracle.com
Oracle Government
Herndon VA
--
http://govt.us.oracle.com/ -- downloadable utilities
Anti-Anti Spam Msg: if you want an answer emailed to you, you have to make it easy to get email to you. Any bounced email will be treated the same way i treat SPAM-- I delete it. Received on Mon Nov 30 1998 - 13:19:19 CST
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