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I have a table in sql 2000 that is storing Financial Tick data. The database
size now appears at about 30GB and I have decided to backup the database and
store the data offsite.

Here is where I am confused about whether only a Database (complete) backup
is necessary or whether I must also include a Transaction log backup for the
most recent data.

1. If I use a complete Database backup only, will all my data be stored on
this? (Even if I have never done a Transaction log backup)

2. My Database size Data.MDF is 500MB and the Log.LDF is 30GB. If I complete
a database Backup can I now get rid of this Log file, or is it also storing
data that is necessary???? I noticed on Books online that it states
following a log file backup that it truncates the inactive portion of the
transaction log, which would hopefully decrease this enormous log file size.

Thank you for your help

"Fred" <Fred@hotmail.com> wrote in message
news:418462d8$1@duster.adelaide.on.net...
> I have a table in sql 2000 that is storing Financial Tick data. The
database
> size now appears at about 30GB and I have decided to backup the database
and
> store the data offsite.
>
> Here is where I am confused about whether only a Database (complete)
backup
> is necessary or whether I must also include a Transaction log backup for
the
> most recent data.

The Full will only be complete up through any committed transaction at the
time of its finish.

Now, if you do a full once a day (say at 1:00 AM), you can restore to that
point.

But let's say your DB crashes at 11:00 PM. You've lost 22 hours worth of
transactions.

If you do a transaction backup say every hour, you could restore up through
the 10:00 PM log and lose less data.

>
> 1. If I use a complete Database backup only, will all my data be stored on
> this? (Even if I have never done a Transaction log backup)

See above.

>
> 2. My Database size Data.MDF is 500MB and the Log.LDF is 30GB. If I
complete
> a database Backup can I now get rid of this Log file, or is it also
storing
> data that is necessary???? I noticed on Books online that it states
> following a log file backup that it truncates the inactive portion of the
> transaction log, which would hopefully decrease this enormous log file
size.

Right.

You have a couple of options here.

If you don't care about transaction log backups (i.e. do the "restore once a
day, don't care if I lose lots of data") then set the DB to simple recovery
mode.

However, generally you DO care about transaction log backups, which means
you should do them.

In that case your log will generally stay much smaller and you can then
shrink it to a reasonable size.

Hope that helps some.


>
> Thank you for your help
>
>

Thank you, starting to make sense now.

I just did a transaction log backup but unfortunately the Log.LDF is still
30GB. I was hoping that it would be extremely small now.

I am assuming that the Log.LDF has all my transactions going back for the
last two months since the databse was created. Is there some method for me
to reduce this file to say on the last couple days of transactions?

Why would SQL not have the option for this huge transaction log to be wiped
when I did the full database backup. Am I missing somethting here on the log
files purpose?

Thanks.



"Greg D. Moore (Strider)" <mooregr_deleteth1s@greenms.com> wrote in message
news:qCZgd.341053$bp1.260186@twister.nyroc.rr.com. ..
>
> "Fred" <Fred@hotmail.com> wrote in message
> news:418462d8$1@duster.adelaide.on.net...
> > I have a table in sql 2000 that is storing Financial Tick data. The
> database
> > size now appears at about 30GB and I have decided to backup the database
> and
> > store the data offsite.
> >
> > Here is where I am confused about whether only a Database (complete)
> backup
> > is necessary or whether I must also include a Transaction log backup for
> the
> > most recent data.
>
> The Full will only be complete up through any committed transaction at the
> time of its finish.
>
> Now, if you do a full once a day (say at 1:00 AM), you can restore to that
> point.
>
> But let's say your DB crashes at 11:00 PM. You've lost 22 hours worth of
> transactions.
>
> If you do a transaction backup say every hour, you could restore up
through
> the 10:00 PM log and lose less data.
>
> >
> > 1. If I use a complete Database backup only, will all my data be stored
on
> > this? (Even if I have never done a Transaction log backup)
>
> See above.
>
> >
> > 2. My Database size Data.MDF is 500MB and the Log.LDF is 30GB. If I
> complete
> > a database Backup can I now get rid of this Log file, or is it also
> storing
> > data that is necessary???? I noticed on Books online that it states
> > following a log file backup that it truncates the inactive portion of
the
> > transaction log, which would hopefully decrease this enormous log file
> size.
>
> Right.
>
> You have a couple of options here.
>
> If you don't care about transaction log backups (i.e. do the "restore once
a
> day, don't care if I lose lots of data") then set the DB to simple
recovery
> mode.
>
> However, generally you DO care about transaction log backups, which means
> you should do them.
>
> In that case your log will generally stay much smaller and you can then
> shrink it to a reasonable size.
>
> Hope that helps some.
>
>
> >
> > Thank you for your help
> >
> >
>
>

I managed to find the information here.
http://support.microsoft.com/default...b;en-us;272318

Backed up the log with TRUNCATE _ONLY and then ran DBCC SHRINKFILE.

Worked like a charm.


"Fred" <Fred@hotmail.com> wrote in message
news:41846b36@duster.adelaide.on.net...
> Thank you, starting to make sense now.
>
> I just did a transaction log backup but unfortunately the Log.LDF is
still
> 30GB. I was hoping that it would be extremely small now.
>
> I am assuming that the Log.LDF has all my transactions going back for the
> last two months since the databse was created. Is there some method for me
> to reduce this file to say on the last couple days of transactions?
>
> Why would SQL not have the option for this huge transaction log to be
wiped
> when I did the full database backup. Am I missing somethting here on the
log
> files purpose?
>
> Thanks.
>
>
>
> "Greg D. Moore (Strider)" <mooregr_deleteth1s@greenms.com> wrote in
message
> news:qCZgd.341053$bp1.260186@twister.nyroc.rr.com. ..
> >
> > "Fred" <Fred@hotmail.com> wrote in message
> > news:418462d8$1@duster.adelaide.on.net...
> > > I have a table in sql 2000 that is storing Financial Tick data. The
> > database
> > > size now appears at about 30GB and I have decided to backup the
database
> > and
> > > store the data offsite.
> > >
> > > Here is where I am confused about whether only a Database (complete)
> > backup
> > > is necessary or whether I must also include a Transaction log backup
for
> > the
> > > most recent data.
> >
> > The Full will only be complete up through any committed transaction at
the
> > time of its finish.
> >
> > Now, if you do a full once a day (say at 1:00 AM), you can restore to
that
> > point.
> >
> > But let's say your DB crashes at 11:00 PM. You've lost 22 hours worth
of
> > transactions.
> >
> > If you do a transaction backup say every hour, you could restore up
> through
> > the 10:00 PM log and lose less data.
> >
> > >
> > > 1. If I use a complete Database backup only, will all my data be
stored
> on
> > > this? (Even if I have never done a Transaction log backup)
> >
> > See above.
> >
> > >
> > > 2. My Database size Data.MDF is 500MB and the Log.LDF is 30GB. If I
> > complete
> > > a database Backup can I now get rid of this Log file, or is it also
> > storing
> > > data that is necessary???? I noticed on Books online that it states
> > > following a log file backup that it truncates the inactive portion of
> the
> > > transaction log, which would hopefully decrease this enormous log file
> > size.
> >
> > Right.
> >
> > You have a couple of options here.
> >
> > If you don't care about transaction log backups (i.e. do the "restore
once
> a
> > day, don't care if I lose lots of data") then set the DB to simple
> recovery
> > mode.
> >
> > However, generally you DO care about transaction log backups, which
means
> > you should do them.
> >
> > In that case your log will generally stay much smaller and you can then
> > shrink it to a reasonable size.
> >
> > Hope that helps some.
> >
> >
> > >
> > > Thank you for your help
> > >
> > >
> >
> >
>
>

To keep your log size manageable in the future, either backup the
transaction log periodically (FULL or BULK_LOGGED recovery model or set the
recovery model to SIMPLE so that committed transactions are periodically
removed from the log. The proper choice depends on your recovery plan as
described by Greg. Once you've setup log backups or use the SIMPLE model,
you'll only need to shrink the log when the log grows unusually large due to
an large transaction.

--
Hope this helps.

Dan Guzman
SQL Server MVP

"Fred" <Fred@hotmail.com> wrote in message
news:41847847$1@duster.adelaide.on.net...
>I managed to find the information here.
> http://support.microsoft.com/default...b;en-us;272318
>
> Backed up the log with TRUNCATE _ONLY and then ran DBCC SHRINKFILE.
>
> Worked like a charm.
>
>
> "Fred" <Fred@hotmail.com> wrote in message
> news:41846b36@duster.adelaide.on.net...
>> Thank you, starting to make sense now.
>>
>> I just did a transaction log backup but unfortunately the Log.LDF is
> still
>> 30GB. I was hoping that it would be extremely small now.
>>
>> I am assuming that the Log.LDF has all my transactions going back for the
>> last two months since the databse was created. Is there some method for
>> me
>> to reduce this file to say on the last couple days of transactions?
>>
>> Why would SQL not have the option for this huge transaction log to be
> wiped
>> when I did the full database backup. Am I missing somethting here on the
> log
>> files purpose?
>>
>> Thanks.
>>
>>
>>
>> "Greg D. Moore (Strider)" <mooregr_deleteth1s@greenms.com> wrote in
> message
>> news:qCZgd.341053$bp1.260186@twister.nyroc.rr.com. ..
>> >
>> > "Fred" <Fred@hotmail.com> wrote in message
>> > news:418462d8$1@duster.adelaide.on.net...
>> > > I have a table in sql 2000 that is storing Financial Tick data. The
>> > database
>> > > size now appears at about 30GB and I have decided to backup the
> database
>> > and
>> > > store the data offsite.
>> > >
>> > > Here is where I am confused about whether only a Database (complete)
>> > backup
>> > > is necessary or whether I must also include a Transaction log backup
> for
>> > the
>> > > most recent data.
>> >
>> > The Full will only be complete up through any committed transaction at
> the
>> > time of its finish.
>> >
>> > Now, if you do a full once a day (say at 1:00 AM), you can restore to
> that
>> > point.
>> >
>> > But let's say your DB crashes at 11:00 PM. You've lost 22 hours worth
> of
>> > transactions.
>> >
>> > If you do a transaction backup say every hour, you could restore up
>> through
>> > the 10:00 PM log and lose less data.
>> >
>> > >
>> > > 1. If I use a complete Database backup only, will all my data be
> stored
>> on
>> > > this? (Even if I have never done a Transaction log backup)
>> >
>> > See above.
>> >
>> > >
>> > > 2. My Database size Data.MDF is 500MB and the Log.LDF is 30GB. If I
>> > complete
>> > > a database Backup can I now get rid of this Log file, or is it also
>> > storing
>> > > data that is necessary???? I noticed on Books online that it states
>> > > following a log file backup that it truncates the inactive portion of
>> the
>> > > transaction log, which would hopefully decrease this enormous log
>> > > file
>> > size.
>> >
>> > Right.
>> >
>> > You have a couple of options here.
>> >
>> > If you don't care about transaction log backups (i.e. do the "restore
> once
>> a
>> > day, don't care if I lose lots of data") then set the DB to simple
>> recovery
>> > mode.
>> >
>> > However, generally you DO care about transaction log backups, which
> means
>> > you should do them.
>> >
>> > In that case your log will generally stay much smaller and you can then
>> > shrink it to a reasonable size.
>> >
>> > Hope that helps some.
>> >
>> >
>> > >
>> > > Thank you for your help
>> > >
>> > >
>> >
>> >
>>
>>
>
>

Fred (Fred@hotmail.com) writes:
> I just did a transaction log backup but unfortunately the Log.LDF is
> still 30GB. I was hoping that it would be extremely small now.
>
> I am assuming that the Log.LDF has all my transactions going back for the
> last two months since the databse was created. Is there some method for me
> to reduce this file to say on the last couple days of transactions?
>
> Why would SQL not have the option for this huge transaction log to be
> wiped when I did the full database backup. Am I missing somethting here
> on the log files purpose?

It is quite clear that it you have a 500 MB data file and a 30 GB log file
that you have not full understanding of the purpose transaction log, yes.

The normal procedures is to backup log at least as frequently as often
you backup the database. Often more frequently. If you do this, the log
will not grow to 30 GB for a database of your size.

SQL Server does not shrink the log automatically, because shrinking
something that will grow again is not a good idea, since growing takes
machine power.

As noted by Greg and Dan, you should make the decision whether you want
full/bulk-logged recovery or simple. If you choose simple, you don't have
to bother about the transaction log, but if the database crashes in the
afternoon, you lose all ticks for that day, assuming that you took a
full backup at midnight. So my guess is that you should stick with full
recovery and backup the translog regularly.


--
Erland Sommarskog, SQL Server MVP, esquel@sommarskog.se

Books Online for SQL Server SP3 at
http://www.microsoft.com/sql/techinf...2000/books.asp