Oracle doesn't move rows unless you reorganize the database. If a row grows
so as to no longer fit in it's current block, then the block is chained
(essentially another physical block is added and the two make one bigger
logical block) and the row just expands into the new space with no change of
rowid. Note that chained blocks are not a good thing. I believe that rowids
will work fine for what Vinay is trying to do with them. Of course this is
always subject to change if Oracle changes the way the database works.
That being said, in all the time I've used Oracle (15 years) I've never gone
down this path of using the rowid. For some reason I have a deep distrust
of this strategy. Perhaps it was when I was an Oracle consultant and
advised people against doing it. Who knows.
Cheers
-----Original Message-----
From: K.V. Vinay Menon [mailto:[EMAIL PROTECTED]]
Sent: Wednesday, June 06, 2001 10:49 AM
To: [EMAIL PROTECTED]
Subject: Re: [JBoss-dev] Fast Updates Based on Row ID
Locks will be in place since the rowid stuff is applicable only for updates
and deletes. selects obviously cannot work with this! Also, to the best of
my knowledge Oracle row ids are fixed unless you move them to new db i.e.
export or stuff.
Vinay
----- Original Message -----
From: "Georg Rehfeld" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Wednesday, June 06, 2001 2:57 PM
Subject: Re: [JBoss-dev] Fast Updates Based on Row ID
> Hi Vinay,
>
> as far as I can remember from my Oracle times using the ROWID is
> only allowed inside transactions and when you got the row with
> SELECT ... FOR UPDATE else the ROWID isn't fixed, but may change,
> when other clients update the row (at least when the update
> causes the row to be moved to another block in the DB, as the
> ROWID in Oracle is the physical address of the row).
>
> I havn't the docs handy, if you have them online, then you might
> search for ROWID until you find that precondition, sorry, but I'm
> pretty sure it exists.
>
> In your code I couldn't find checks for either, at least the
> <select-for-update> JAWS option should be available and checked
> for true, migth be this is enough checking there, as select for
> update is valid inside transactions only anyway.
>
> regards
> Georg
> ___ ___
> | + | |__ Georg Rehfeld Woltmanstr. 12 20097 Hamburg
> |_|_\ |___ [EMAIL PROTECTED] +49 (40) 23 53 27 10
>
>
>
> _______________________________________________
> Jboss-development mailing list
> [EMAIL PROTECTED]
> http://lists.sourceforge.net/lists/listinfo/jboss-development
_______________________________________________
Jboss-development mailing list
[EMAIL PROTECTED]
http://lists.sourceforge.net/lists/listinfo/jboss-development
_______________________________________________
Jboss-development mailing list
[EMAIL PROTECTED]
http://lists.sourceforge.net/lists/listinfo/jboss-development
