Comments below.
HJR
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Resources for Oracle: http://www.hjrdba.com
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"Andrej" <andrej611_at_wp.pl> wrote in message
news:9v0dag$9a1$1_at_korweta.task.gda.pl...
> Hello,
>
> I am looking for the following info concering Oracle internals:
> - how does Oracle know what blocks are assigned to what tables ? does is
> blindly scan throug all the blocks ?
No, it holds that information in data dictionary tables. Specifically, UET$
records what extents exist, and who owns them. Tables such as OBJ$ and TAB$
also come into play. In locally managed tablespace, a bitmap at the header
of the tablespace indicates whether a block is reserved for use or not.
Data dictionary entries still say which object owns which block.
> - I know a single block can hold data for different segments.
No it can't.
>So where is a
> glue that holds a blocks/extents of a segment toegether ?
There is no such substance.
> - what is internal structure of a datafile ? I am not asking to know the
(c)
> details but just a big picture. Once I did an append to one of a datafiles
> with tar ...
>
> Please, point me to some reference on Oracle internals.
Steve Adams has a book. O'Reilly, something like 'internal services for
Oracle'. Go to his web site (www.ixora.com.au) and you'll be able to see it
(and its accurate title, which I've forgotten) under the 'Resources' link).
Regards
HJR
>
> Just beeing courious,
> Andrej
>
>
Received on Sun Dec 09 2001 - 13:44:48 CST
