Re: OFA and file extension naming conventions

So do you believe that oracle should keep calling tempfiles datafiles and that it is a good naming convention even though they can't be hot backed up and that oracle treats them differently to dba_data_files?

One can no longer say that you only need to backup datafiles.

"Howard J. Rogers" <hjr_at_dizwell.com> wrote in message news:40627e93$0$31904$afc38c87_at_news.optusnet.com.au...
|
| "Snid" <snid_at_snider.sno> wrote in message
| news:c3tla8$tum$1_at_bunyip.cc.uq.edu.au...
| > Hmmn, Ok.
| >
| > I guess I just look at tempfiles (files that exist in dba_temp_files)
| > differently to datafiles (files that exist in dba_data_files) as you
don't
| > really need to back them up.
|
|
| Not only do you not "need" to back them up, you can't back them up. You
| cannot issue 'alter tablespace X begin backup' commands, when the data
files
| associated with that tablespace are known to be tempfiles.
|
| So what, however? You can't take a datafile called system01.dbf offline or
| make system01.dbf read-only either.
|
| Functionality is one thing, and the physics are something else.
Physically,
| they're data files.
|
| > Also, the fact that oracle segregates tempfiles from datafiles by using
| the
| > two tables from above makes me think of them as different so I thought
| that
| > maybe a different extension might be applicable.
|
| The reason it did that, fundamentally, goes back to the inability to put a
| temp file into hot backup mode. A lot of people perform user-managed
backups
| via scripts, and those scripts dynamically work out what to backup by
| looking at (for example) v$datafile. It obviously wouldn't do to have
| entries appearing in that view (and hence in the dynamically-created
backup
| scripts) which will produce errors when 'begin backup' commands are
| attempted against them. Hence the need to separate them out from each
other.
|
| But again, just because I see table A, B, C and D when I query ALL_TABLES
| and only tables A & C when I query USER_TABLES doesn't mean that B and D
| aren't really tables.
|
| Regards
| HJR
|
|
|
| >
| > But yes, oracle does call tempfiles temporary datafiles or vice versa.
| >
| >
| >
| >
| >
| > "Howard J. Rogers" <hjr_at_dizwell.com> wrote in message
| > news:40624469$0$31901$afc38c87_at_news.optusnet.com.au...
| > |
| > | "Snid" <snid_at_snider.sno> wrote in message
| > | news:c3tg0n$354$1_at_bunyip.cc.uq.edu.au...
| > | > Under OFA it says that data files (datafiles) should end with a .dbf
| > | > extension; however, it doesn't mention what temporary files
| (tempfiles,
| > | temp
| > | > files) should end in.
| > | >
| > | > I don't think that tempfiles should end with a .dbf extension as
they
| > | aren't
| > | > datafiles.
| > |
| > | Yes they are. What makes you think they're not? The contents of the
| files
| > | are different, for sure, in the sense that you don't care about it on
a
| > | long-term basis. But even then, they've got Oracle blocks inside them
| with
| > | headers and so on.
| > |
| > | The only difference between a "normal" data file and a temp file is
that
| > the
| > | latter are created initially sparse (like when you touch a file in
| *nix).
| > | But once people start using the file for sorts etc, then the thing
gets
| > | internally formatted exactly like any other data file would.
| > |
| > | So it's a data file, and it should get a dbf extension.
| > |
| > | Regards
| > | HJR
| > |
| > |
| >
| >
|
|
Received on Thu Mar 25 2004 - 17:43:39 CST