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Home -> Community -> Mailing Lists -> Oracle-L -> RE: MS SQL hasn't given up!
If you are an Oracle DBA and management switches to SQL Server no Oracle DBA
in the world is going to sway that decision.
By the the time an Oracle DBA will hear about that he or she is already
slated for "re-tooling".
You were very lucky to be able to present to management.
Many times the deal is over and you are sent to MS-SQL classes or quit.
Another example of a "DBMH" system. (decision by marketing hype)
Frankly you can't have a mission critical enterprise class RDBMS on a unreliable, unsecure OS.
(ouch)
BRad O.
-----Original Message-----
Sent: Friday, February 28, 2003 3:35 PM
To: Multiple recipients of list ORACLE-L
The txn log is just a separate database file(s) and they can autogrow in increments (MB or %). The growth can be unrestricted or restricted to a fixed MB size. Though command line TSQL can create the files with space allocated in units (KB/MB/GB/TB). The wizard isn't quite as flexible. There can also be multiple transaction log files though I believe the virtual log files (logs within logs) extended through the additional files as needed as opposed to the circular log jumping that happens in Oracle.
I think it is important as Oracle DBA's we have at least a conceptual knowledge of what SQL Server can and cannot do. So when management says they
want to switch to SQL Server you have something to back up your opinions. I ran into this where the management was MSS/Win2K focused to the max I had to
battle against them and the MS marketing guy. I won but it was a lot of work
to prove my case. Actually, used application porting time/costs/metrics as DBMS/OS capabilities was a much harder sell.
>From: STEVE OLLIG <sollig_at_lifetouch.com>
>Reply-To: ORACLE-L_at_fatcity.com
>To: Multiple recipients of list ORACLE-L <ORACLE-L_at_fatcity.com>
>Subject: RE: MS SQL hasn't given up!
>Date: Fri, 28 Feb 2003 12:49:29 -0800
>
>no problem Rich. the transaction log mirroring can be done by the DBMS.
>and SQueal Server has disk devices much like a tablespace that can be
>placed
>on different disks and such. transaction logs are kind of like tables in
>that they must be placed in a device. so yes, these mirrored transaction
>logs can be kept apart and "safe".
>
>Rachel's comment is also accurate however. if things go way wrong (usually
>happens to a novice dba) the transaction log can get stuffed so full that
>there's no way to "archive" it and you end up "truncating" it. users tend
>not to like it when they can't do DML ;-) anyway, once a transaction log
>has been truncated there is no transaction recovery until the next database
>backup completes. and yes - the database backup utility does hot backups.
>
> > -----Original Message-----
> > From: Jesse, Rich [SMTP:Rich.Jesse_at_qtiworld.com]
> > Sent: Friday, February 28, 2003 1:47 PM
> > To: Multiple recipients of list ORACLE-L
> > Subject: RE: MS SQL hasn't given up!
> >
> > Steve, when you say "mirror" are the writes duplicated from SQueaL
>Server
> > or
> > hardware? My DBA instructor had distributed some e-mails from a student
> > who
> > left the mirroring of redos up to hardware. One controller firmware
>patch
> > is all it took to corrupt both copies of the redos.
> >
> > So, if the mirror is done at the hardware level, it wouldn't be the same
> > as
> > Oracle. Also, if the TX logs are in the DB, how separated can the
>mirrors
> > be?
> >
> > Hope this isn't getting too off-topic. I just want to make sure that
>I'm
> > not burning any bridges by refusing to let SQueaL Server get any more
>DBs
> > here...
> >
> > Thx!
> > Rich
> >
> >
> > Rich Jesse System/Database Administrator
> > rich.jesse_at_qtiworld.com Quad/Tech International, Sussex, WI
>USA
> >
> >
> > -----Original Message-----
> > Sent: Friday, February 28, 2003 1:19 PM
> > To: Multiple recipients of list ORACLE-L
> >
> >
> > Rich - on your first point - that's why you would choose to mirror the
> > transaction log in SQeal Server. Same effect.
> >
> > the transaction log is a fixed size. it can be extended while the db is
> > online. but shrinking it is quite a bother (at least was back in the
>day
> > -
> > it's been a while). if the transaction log fills up all DML stops.
> > database still recoverable though. just need to clean out or extend the
> > log
> > and all is well again.
> >
> > no snapshot too old errors though ;-)
> >
> > > -----Original Message-----
> > > From: Jesse, Rich [SMTP:Rich.Jesse_at_qtiworld.com]
> > > Sent: Friday, February 28, 2003 12:14 PM
> > > To: Multiple recipients of list ORACLE-L
> > > Subject: RE: MS SQL hasn't given up!
> > >
> > > Yes and no. If your logs are backed up every 30 minutes, then you are
> > > effectively saying that you are willing to lose up to 30 minutes of
> > > transactions, in the event of failure on the TX logs (e.g. hardware).
> > > OTOH,
> > > Oracle can easily be made to be completely recoverable up to the last
> > > transaction ("no data lost") by duplicating, triplicating, etc. both
>the
> > > online redos and the archives.
> > >
> > > Also, isn't the transaction log area in SQueaL Server in the DB itself
> > and
> > > at a fixed size (as opposed to Oracle, where you can add redo groups
> > > on-the-fly)? In other words, if it fills up, what happens? Does it
>get
> > > overwritten or does the DB continue in an unrecoverable mode?
> > >
> > > Trying to understand more of this wonderful Enterprise product...
> > >
> > > Rich
> > --
> > Please see the official ORACLE-L FAQ: http://www.orafaq.net
> > --
> > Author: Jesse, Rich
> > INET: Rich.Jesse_at_qtiworld.com
> >
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>--
>Please see the official ORACLE-L FAQ: http://www.orafaq.net
>--
>Author: STEVE OLLIG
> INET: sollig_at_lifetouch.com
>
>Fat City Network Services -- 858-538-5051 http://www.fatcity.com
>San Diego, California -- Mailing list and web hosting services
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-- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: david davis INET: ddoralist_at_hotmail.com Fat City Network Services -- 858-538-5051 http://www.fatcity.com San Diego, California -- Mailing list and web hosting services --------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing). -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Odland, Brad INET: Brad.Odland_at_qtiworld.com Fat City Network Services -- 858-538-5051 http://www.fatcity.com San Diego, California -- Mailing list and web hosting services --------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing).Received on Fri Feb 28 2003 - 16:45:27 CST
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