Re: Oracle basics

Try to cut down on the use of extraneous white space.

There's no 'create database' command, because that was issued a long while back. When you issue the create database command, you get one system tablespace, comprised of one system datafile. Every *other* tablespace (and datafile) has to be added in manually by issuing 'create tablespace' commands.

Physically, an Oracle database is a collection of control files, data files and online redo logs, as you said. But yes, a weak-ish logical description of an Oracle database is that it is a collection of one or more tablespaces (the "one" it must be made up of is, of course, SYSTEM).

Regards
HJR "Anon" <Anon_at_invisible.com> wrote in message news:hSmq7.74724$bY5.353715_at_news-server.bigpond.net.au...
> Hello,
>
>
>
> I have a quick. I can't seem to find a deffinative answer on this and I am
> sure that there are a number of other people who must also be suffering
the
> same confusion.
>
>
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> Basically, I need some help understanding the structure of Oracle objects,
> both physical and logical.
>
>
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> People seem to refer to a database as a physical set of files that form a
> working data container and objects for Oracle. i.e. control files, redo
logs
> & data files. I repeatedly see the fact that you can not see a tablespace
at
> OS level as it is a logical structure, not physical. However, when I issue
> the following command:
>
>
>
> create tablespace test datafile
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> '/apps/oracle/data/test.dbf' size 200M
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> default storage (
>
> initial 8k
>
> next 256k
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> pctincrease 0
>
> minextents 1
>
> );
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>
>
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> It does create a physical file which I can populate with tables, views
> etc...
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> At this point I have not issued the create database command and therefore
> wonder where it comes in to play and why I haven't had to issue the create
> database command. Is it to do with the default storage line ? Is this
> creating a database for me without my knowledge ?
>
>
>
> If this is the case, then you would draw the conclusion that a tablespace
is
> a logical division of a physical database. Is this correct ?
>
>
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> Any clarity on this would be appreciated.
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Received on Thu Sep 20 2001 - 13:45:28 CDT