August 24, 2011 at 6:53 am
Hello,
I'm new to SQL servers and I need a little help.
I created a backup task by right-clicking the database I want to back up. I also created a maintenance plan to back it up. I noticed that the file produced by the maintenance plan is about 14 times smaller than the file produced by the back up task. They are both supposed to be full backup!
The backup is to be done weekly on Monday through Friday. The first backup file (created on 26-Jul-2011) is 540MB in size and it grows gradually to 580MB for the backup file of 12-Aug-2011. Then on 16-Aug-2011 the size of the backup file is 1.1GB and there is another backup file that is almost 590MB and then it grows again to about 600MB on 19-Aug-2011.
On 22-Aug-2011, the backup file is almost 6.4GB and on 23-Aug-2011 the size of the file is 10.4GB! I know the data didn't grow this much in such a short time and I can't explain why the huge difference in backup files produced over such a short time.
This is why I would like to completely remove the backup that is configured through the Tasks-->Back up menu and start over. I would most likely want to remove the maintenance plan backup job as well, just to be sure, but we'll see that in the next few days.
Thank you kindly,
August 24, 2011 at 6:59 am
Is your database in Full recovery mode? How often, and when, do you back up your transaction log?
John
August 24, 2011 at 8:27 am
Hi John,
Good questions. I'm not sure I can answer that because I don't know. I'm very new to SQL Server.
Can you provide details how to find out?
Thank you,
August 24, 2011 at 8:32 am
SELECT recovery_model_desc
FROM master.sys.databases
WHERE [name] = '<InsertYourDatabaseNameHere>'
As for backing up the log, I imagine that if you don't know whether you do it, then you don't do it. When you back up the database, the contents of the log get backed up as well. And the log will keep growing until you do a log backup. I'd bet that this is why your backup file keeps getting bigger.
John
August 24, 2011 at 9:05 am
Hi John,
Thank you for your help.
I run your query and I got SIMPLE as a result.
What does simple recovery model mean?
You are most likely right about backing up the log. In that case, can I add it to my Maintenance Plan backup? How do I do that?
Thank you,
August 25, 2011 at 1:29 am
Search this site (or elsewhere) for "simple recovery model" and read about recovery models and backing up the transaction logs. One of the things you'll notice is that you don't need to, nor can you, back up the transaction log in simple mode. So this doesn't explain the problem you're having.
If you run DBCC SQLPERF(LOGSPACE) after one of the large backups, what do you get?
I think you really need to get someone in to help you with the basics for a couple of days - just to get your backups set up and explain the things that are essential for you to know. You can't cover all that in a couple of forum posts, unfortunately.
John
August 25, 2011 at 2:19 am
arie01 (8/24/2011)
On 22-Aug-2011, the backup file is almost 6.4GB and on 23-Aug-2011 the size of the file is 10.4GB! I know the data didn't grow this much in such a short time and I can't explain why the huge difference in backup files produced over such a short time.
sounds like it could be a differential backup thats running. Execute the following and post the results back
USE MSDB
select bs.database_name, bs.backup_size / 1048576 as SizeInMBs, bs.server_name,
case bs.type
when 'D' then 'Full'
when 'I' then 'Diff'
when 'L' then 'Log'
else bs.type
end as Type, bs.backup_finish_date,
bf.backed_up_page_count, bf.physical_name from dbo.backupset bs
left outer join dbo.backupfile bf on bs.backup_set_id = bf.backup_set_id
-----------------------------------------------------------------------------------------------------------
"Ya can't make an omelette without breaking just a few eggs" 😉
August 25, 2011 at 7:22 am
Hi Perry and thankyou for replying to my post.
I figured out a part of my problem. One of the two backup jobs configued is appending the backup file to the previous one if it finds the same name in the backup folder. That's why I asked how can I remove a backup job configured throuigh the Tasks-->Back up menu of a database. I tried to remove the append but at the configuration page there is only an option to overwrite existing files with the same name. This would mean that I will have to run a script to move the backup file from the backup folder to another folder if I want to keep a week back or so. The other option would be to modify the file name so that it includes the date and time the backup was running. How do I do that though???
So yesterday I remove the 10GB file from the backup folder and this morning I found two backup files (for the two backup jobs with different names) identical in size.
Here is the results of your quary. I simply changed the databse and server names for that post, the rest is actual data.
Thank you,
DB_Name SizeInMBsServer_NameTypeBackup_Finish_DateBacked_up_Page CountPhysical_Name
DB_Name493.08398437Server_Name\SQL08Full2011-07-12 17:51:36.00063080E:\SQLDATA\DB_Name.mdf
DB_Name493.08398437Server_Name\SQL08Full2011-07-12 17:51:36.0005E:\SQLDATA\DB_Name_1.ldf
DB_Name496.08398437Server_Name\SQL08Full2011-07-14 08:53:39.00063440E:\SQLDATA\DB_Name.mdf
DB_Name496.08398437Server_Name\SQL08Full2011-07-14 08:53:39.0007E:\SQLDATA\DB_Name_1.ldf
DB_Name499.08398437Server_Name\SQL08Full2011-07-14 20:02:39.00063808E:\SQLDATA\DB_Name.mdf
DB_Name499.08398437Server_Name\SQL08Full2011-07-14 20:02:39.0006E:\SQLDATA\DB_Name_1.ldf
DB_Name503.08398437Server_Name\SQL08Full2011-07-18 11:43:45.00064360E:\SQLDATA\DB_Name.mdf
DB_Name503.08398437Server_Name\SQL08Full2011-07-18 11:43:45.0004E:\SQLDATA\DB_Name_1.ldf
DB_Name504.14648437Server_Name\SQL08Full2011-07-18 12:48:07.00064472E:\SQLDATA\DB_Name.mdf
DB_Name504.14648437Server_Name\SQL08Full2011-07-18 12:48:07.0009E:\SQLDATA\DB_Name_1.ldf
DB_Name511.08398437Server_Name\SQL08Full2011-07-19 17:07:03.00065384E:\SQLDATA\DB_Name.mdf
DB_Name511.08398437Server_Name\SQL08Full2011-07-19 17:07:03.0006E:\SQLDATA\DB_Name_1.ldf
DB_Name513.08398437Server_Name\SQL08Full2011-07-20 16:17:51.00065624E:\SQLDATA\DB_Name.mdf
DB_Name513.08398437Server_Name\SQL08Full2011-07-20 16:17:51.0005E:\SQLDATA\DB_Name_1.ldf
DB_Name513.08398437Server_Name\SQL08Full2011-07-20 17:15:52.00065632E:\SQLDATA\DB_Name.mdf
DB_Name513.08398437Server_Name\SQL08Full2011-07-20 17:15:52.0003E:\SQLDATA\DB_Name_1.ldf
DB_Name513.08300781Server_Name\SQL08Full2011-07-20 18:51:47.00065640E:\SQLDATA\DB_Name.mdf
DB_Name513.08300781Server_Name\SQL08Full2011-07-20 18:51:47.0005E:\SQLDATA\DB_Name_1.ldf
DB_Name516.08398437Server_Name\SQL08Full2011-07-22 08:41:10.00065992E:\SQLDATA\DB_Name.mdf
DB_Name516.08398437Server_Name\SQL08Full2011-07-22 08:41:10.0005E:\SQLDATA\DB_Name_1.ldf
DB_Name525.08398437Server_Name\SQL08Full2011-07-26 12:16:46.00067104E:\SQLDATA\DB_Name.mdf
DB_Name525.08398437Server_Name\SQL08Full2011-07-26 12:16:46.0008E:\SQLDATA\DB_Name_1.ldf
DB_Name528.08398437Server_Name\SQL08Full2011-07-26 20:00:12.00067560E:\SQLDATA\DB_Name.mdf
DB_Name528.08398437Server_Name\SQL08Full2011-07-26 20:00:12.0003E:\SQLDATA\DB_Name_1.ldf
DB_Name528.08398437Server_Name\SQL08Full2011-07-26 20:00:20.00067560E:\SQLDATA\DB_Name.mdf
DB_Name528.08398437Server_Name\SQL08Full2011-07-26 20:00:20.0002E:\SQLDATA\DB_Name_1.ldf
DB_Name533.08398437Server_Name\SQL08Full2011-07-27 20:00:13.00068136E:\SQLDATA\DB_Name.mdf
DB_Name533.08398437Server_Name\SQL08Full2011-07-27 20:00:13.0007E:\SQLDATA\DB_Name_1.ldf
DB_Name533.08300781Server_Name\SQL08Full2011-07-27 20:00:24.00068136E:\SQLDATA\DB_Name.mdf
DB_Name533.08300781Server_Name\SQL08Full2011-07-27 20:00:24.0002E:\SQLDATA\DB_Name_1.ldf
DB_Name533.08398437Server_Name\SQL08Full2011-07-27 20:00:35.00068136E:\SQLDATA\DB_Name.mdf
DB_Name533.08398437Server_Name\SQL08Full2011-07-27 20:00:35.0002E:\SQLDATA\DB_Name_1.ldf
DB_Name537.08300781Server_Name\SQL08Full2011-07-28 20:00:13.00068640E:\SQLDATA\DB_Name.mdf
DB_Name537.08300781Server_Name\SQL08Full2011-07-28 20:00:13.0003E:\SQLDATA\DB_Name_1.ldf
DB_Name537.08398437Server_Name\SQL08Full2011-07-28 20:00:26.00068640E:\SQLDATA\DB_Name.mdf
DB_Name537.08398437Server_Name\SQL08Full2011-07-28 20:00:26.0002E:\SQLDATA\DB_Name_1.ldf
DB_Name538.08300781Server_Name\SQL08Full2011-07-29 12:17:49.00068752E:\SQLDATA\DB_Name.mdf
DB_Name538.08300781Server_Name\SQL08Full2011-07-29 12:17:49.0003E:\SQLDATA\DB_Name_1.ldf
DB_Name538.08300781Server_Name\SQL08Full2011-07-29 12:21:30.00068752E:\SQLDATA\DB_Name.mdf
DB_Name538.08300781Server_Name\SQL08Full2011-07-29 12:21:30.0003E:\SQLDATA\DB_Name_1.ldf
DB_Name538.08300781Server_Name\SQL08Full2011-07-29 12:26:51.00068752E:\SQLDATA\DB_Name.mdf
DB_Name538.08300781Server_Name\SQL08Full2011-07-29 12:26:51.0004E:\SQLDATA\DB_Name_1.ldf
DB_Name539.08398437Server_Name\SQL08Full2011-07-29 20:00:12.00068880E:\SQLDATA\DB_Name.mdf
DB_Name539.08398437Server_Name\SQL08Full2011-07-29 20:00:12.0008E:\SQLDATA\DB_Name_1.ldf
DB_Name539.08398437Server_Name\SQL08Full2011-07-29 20:00:21.00068880E:\SQLDATA\DB_Name.mdf
DB_Name539.08398437Server_Name\SQL08Full2011-07-29 20:00:21.0001E:\SQLDATA\DB_Name_1.ldf
DB_Name539.08398437Server_Name\SQL08Full2011-07-29 20:00:31.00068880E:\SQLDATA\DB_Name.mdf
DB_Name539.08398437Server_Name\SQL08Full2011-07-29 20:00:31.0001E:\SQLDATA\DB_Name_1.ldf
DB_Name545.08300781Server_Name\SQL08Full2011-08-01 20:00:12.00069640E:\SQLDATA\DB_Name.mdf
DB_Name545.08300781Server_Name\SQL08Full2011-08-01 20:00:12.0006E:\SQLDATA\DB_Name_1.ldf
DB_Name545.08300781Server_Name\SQL08Full2011-08-01 20:00:25.00069640E:\SQLDATA\DB_Name.mdf
DB_Name545.08300781Server_Name\SQL08Full2011-08-01 20:00:25.0001E:\SQLDATA\DB_Name_1.ldf
DB_Name545.08398437Server_Name\SQL08Full2011-08-01 20:00:37.00069640E:\SQLDATA\DB_Name.mdf
DB_Name545.08398437Server_Name\SQL08Full2011-08-01 20:00:37.0001E:\SQLDATA\DB_Name_1.ldf
DB_Name548.08300781Server_Name\SQL08Full2011-08-02 20:00:12.00070056E:\SQLDATA\DB_Name.mdf
DB_Name548.08300781Server_Name\SQL08Full2011-08-02 20:00:12.0006E:\SQLDATA\DB_Name_1.ldf
DB_Name548.08398437Server_Name\SQL08Full2011-08-02 20:00:22.00070056E:\SQLDATA\DB_Name.mdf
DB_Name548.08398437Server_Name\SQL08Full2011-08-02 20:00:22.0001E:\SQLDATA\DB_Name_1.ldf
DB_Name551.08300781Server_Name\SQL08Full2011-08-03 20:00:13.00070464E:\SQLDATA\DB_Name.mdf
DB_Name551.08300781Server_Name\SQL08Full2011-08-03 20:00:13.0002E:\SQLDATA\DB_Name_1.ldf
DB_Name551.08300781Server_Name\SQL08Full2011-08-03 20:00:24.00070464E:\SQLDATA\DB_Name.mdf
DB_Name551.08300781Server_Name\SQL08Full2011-08-03 20:00:24.0001E:\SQLDATA\DB_Name_1.ldf
DB_Name551.08398437Server_Name\SQL08Full2011-08-03 20:00:35.00070464E:\SQLDATA\DB_Name.mdf
DB_Name551.08398437Server_Name\SQL08Full2011-08-03 20:00:35.0002E:\SQLDATA\DB_Name_1.ldf
DB_Name553.08300781Server_Name\SQL08Full2011-08-04 20:00:13.00070688E:\SQLDATA\DB_Name.mdf
DB_Name553.08300781Server_Name\SQL08Full2011-08-04 20:00:13.0002E:\SQLDATA\DB_Name_1.ldf
DB_Name553.08398437Server_Name\SQL08Full2011-08-04 20:00:25.00070688E:\SQLDATA\DB_Name.mdf
DB_Name553.08398437Server_Name\SQL08Full2011-08-04 20:00:25.0002E:\SQLDATA\DB_Name_1.ldf
DB_Name554.08300781Server_Name\SQL08Full2011-08-05 20:00:11.00070816E:\SQLDATA\DB_Name.mdf
DB_Name554.08300781Server_Name\SQL08Full2011-08-05 20:00:11.0001E:\SQLDATA\DB_Name_1.ldf
DB_Name554.08300781Server_Name\SQL08Full2011-08-05 20:00:24.00070816E:\SQLDATA\DB_Name.mdf
DB_Name554.08300781Server_Name\SQL08Full2011-08-05 20:00:24.0002E:\SQLDATA\DB_Name_1.ldf
DB_Name554.08398437Server_Name\SQL08Full2011-08-05 20:00:34.00070816E:\SQLDATA\DB_Name.mdf
DB_Name554.08398437Server_Name\SQL08Full2011-08-05 20:00:34.0002E:\SQLDATA\DB_Name_1.ldf
DB_Name557.08300781Server_Name\SQL08Full2011-08-08 20:00:15.00071216E:\SQLDATA\DB_Name.mdf
DB_Name557.08300781Server_Name\SQL08Full2011-08-08 20:00:15.0007E:\SQLDATA\DB_Name_1.ldf
DB_Name557.08300781Server_Name\SQL08Full2011-08-08 20:00:28.00071216E:\SQLDATA\DB_Name.mdf
DB_Name557.08300781Server_Name\SQL08Full2011-08-08 20:00:28.0002E:\SQLDATA\DB_Name_1.ldf
DB_Name557.08398437Server_Name\SQL08Full2011-08-08 20:00:41.00071216E:\SQLDATA\DB_Name.mdf
DB_Name557.08398437Server_Name\SQL08Full2011-08-08 20:00:41.0002E:\SQLDATA\DB_Name_1.ldf
DB_Name558.08300781Server_Name\SQL08Full2011-08-09 20:00:14.00071416E:\SQLDATA\DB_Name.mdf
DB_Name558.08300781Server_Name\SQL08Full2011-08-09 20:00:14.0005E:\SQLDATA\DB_Name_1.ldf
DB_Name558.08398437Server_Name\SQL08Full2011-08-09 20:00:26.00071416E:\SQLDATA\DB_Name.mdf
DB_Name558.08398437Server_Name\SQL08Full2011-08-09 20:00:26.0002E:\SQLDATA\DB_Name_1.ldf
DB_Name562.08300781Server_Name\SQL08Full2011-08-10 20:00:14.00071888E:\SQLDATA\DB_Name.mdf
DB_Name562.08300781Server_Name\SQL08Full2011-08-10 20:00:14.0004E:\SQLDATA\DB_Name_1.ldf
DB_Name562.08300781Server_Name\SQL08Full2011-08-10 20:00:27.00071888E:\SQLDATA\DB_Name.mdf
DB_Name562.08300781Server_Name\SQL08Full2011-08-10 20:00:27.0002E:\SQLDATA\DB_Name_1.ldf
DB_Name562.08398437Server_Name\SQL08Full2011-08-10 20:00:37.00071888E:\SQLDATA\DB_Name.mdf
DB_Name562.08398437Server_Name\SQL08Full2011-08-10 20:00:37.0002E:\SQLDATA\DB_Name_1.ldf
DB_Name565.08300781Server_Name\SQL08Full2011-08-11 20:00:14.00072248E:\SQLDATA\DB_Name.mdf
DB_Name565.08300781Server_Name\SQL08Full2011-08-11 20:00:14.0001E:\SQLDATA\DB_Name_1.ldf
DB_Name565.08398437Server_Name\SQL08Full2011-08-11 20:00:25.00072248E:\SQLDATA\DB_Name.mdf
DB_Name565.08398437Server_Name\SQL08Full2011-08-11 20:00:25.0002E:\SQLDATA\DB_Name_1.ldf
DB_Name567.08300781Server_Name\SQL08Full2011-08-12 20:00:13.00072456E:\SQLDATA\DB_Name.mdf
DB_Name567.08300781Server_Name\SQL08Full2011-08-12 20:00:13.0001E:\SQLDATA\DB_Name_1.ldf
DB_Name567.08300781Server_Name\SQL08Full2011-08-12 20:00:26.00072456E:\SQLDATA\DB_Name.mdf
DB_Name567.08300781Server_Name\SQL08Full2011-08-12 20:00:26.0001E:\SQLDATA\DB_Name_1.ldf
DB_Name567.08398437Server_Name\SQL08Full2011-08-12 20:00:37.00072456E:\SQLDATA\DB_Name.mdf
DB_Name567.08398437Server_Name\SQL08Full2011-08-12 20:00:37.0001E:\SQLDATA\DB_Name_1.ldf
DB_Name573.08300781Server_Name\SQL08Full2011-08-15 20:00:14.00073224E:\SQLDATA\DB_Name.mdf
DB_Name573.08300781Server_Name\SQL08Full2011-08-15 20:00:14.0006E:\SQLDATA\DB_Name_1.ldf
DB_Name573.08300781Server_Name\SQL08Full2011-08-15 20:00:24.00073224E:\SQLDATA\DB_Name.mdf
DB_Name573.08300781Server_Name\SQL08Full2011-08-15 20:00:24.0002E:\SQLDATA\DB_Name_1.ldf
DB_Name573.08398437Server_Name\SQL08Full2011-08-15 20:00:36.00073224E:\SQLDATA\DB_Name.mdf
DB_Name573.08398437Server_Name\SQL08Full2011-08-15 20:00:36.0002E:\SQLDATA\DB_Name_1.ldf
DB_Name574.08300781Server_Name\SQL08Full2011-08-16 11:51:55.00073464E:\SQLDATA\DB_Name.mdf
DB_Name574.08300781Server_Name\SQL08Full2011-08-16 11:51:55.0007E:\SQLDATA\DB_Name_1.ldf
DB_Name576.08300781Server_Name\SQL08Full2011-08-16 20:00:11.00073688E:\SQLDATA\DB_Name.mdf
DB_Name576.08300781Server_Name\SQL08Full2011-08-16 20:00:11.0006E:\SQLDATA\DB_Name_1.ldf
DB_Name576.08398437Server_Name\SQL08Full2011-08-16 20:00:22.00073688E:\SQLDATA\DB_Name.mdf
DB_Name576.08398437Server_Name\SQL08Full2011-08-16 20:00:22.0001E:\SQLDATA\DB_Name_1.ldf
DB_Name580.08300781Server_Name\SQL08Full2011-08-17 20:00:13.00074192E:\SQLDATA\DB_Name.mdf
DB_Name580.08300781Server_Name\SQL08Full2011-08-17 20:00:13.0003E:\SQLDATA\DB_Name_1.ldf
DB_Name580.08300781Server_Name\SQL08Full2011-08-17 20:00:24.00074192E:\SQLDATA\DB_Name.mdf
DB_Name580.08300781Server_Name\SQL08Full2011-08-17 20:00:24.0002E:\SQLDATA\DB_Name_1.ldf
DB_Name580.08398437Server_Name\SQL08Full2011-08-17 20:00:33.00074192E:\SQLDATA\DB_Name.mdf
DB_Name580.08398437Server_Name\SQL08Full2011-08-17 20:00:33.0001E:\SQLDATA\DB_Name_1.ldf
DB_Name583.08300781Server_Name\SQL08Full2011-08-18 20:00:11.00074568E:\SQLDATA\DB_Name.mdf
DB_Name583.08300781Server_Name\SQL08Full2011-08-18 20:00:11.0006E:\SQLDATA\DB_Name_1.ldf
DB_Name583.08398437Server_Name\SQL08Full2011-08-18 20:00:21.00074568E:\SQLDATA\DB_Name.mdf
DB_Name583.08398437Server_Name\SQL08Full2011-08-18 20:00:21.0002E:\SQLDATA\DB_Name_1.ldf
DB_Name586.08300781Server_Name\SQL08Full2011-08-19 20:00:14.00075000E:\SQLDATA\DB_Name.mdf
DB_Name586.08300781Server_Name\SQL08Full2011-08-19 20:00:14.0002E:\SQLDATA\DB_Name_1.ldf
DB_Name586.08300781Server_Name\SQL08Full2011-08-19 20:00:28.00075000E:\SQLDATA\DB_Name.mdf
DB_Name586.08300781Server_Name\SQL08Full2011-08-19 20:00:28.0001E:\SQLDATA\DB_Name_1.ldf
DB_Name586.08398437Server_Name\SQL08Full2011-08-19 20:00:41.00075000E:\SQLDATA\DB_Name.mdf
DB_Name586.08398437Server_Name\SQL08Full2011-08-19 20:00:41.0002E:\SQLDATA\DB_Name_1.ldf
DB_Name592.08300781Server_Name\SQL08Full2011-08-22 20:00:17.00075680E:\SQLDATA\DB_Name.mdf
DB_Name592.08300781Server_Name\SQL08Full2011-08-22 20:00:17.0004E:\SQLDATA\DB_Name_1.ldf
DB_Name592.08300781Server_Name\SQL08Full2011-08-22 20:00:32.00075680E:\SQLDATA\DB_Name.mdf
DB_Name592.08300781Server_Name\SQL08Full2011-08-22 20:00:32.0001E:\SQLDATA\DB_Name_1.ldf
DB_Name593.08398437Server_Name\SQL08Full2011-08-23 14:03:32.00075784E:\SQLDATA\DB_Name.mdf
DB_Name593.08398437Server_Name\SQL08Full2011-08-23 14:03:32.0005E:\SQLDATA\DB_Name_1.ldf
DB_Name594.08300781Server_Name\SQL08Full2011-08-23 20:00:12.00075960E:\SQLDATA\DB_Name.mdf
DB_Name594.08300781Server_Name\SQL08Full2011-08-23 20:00:12.0007E:\SQLDATA\DB_Name_1.ldf
DB_Name598.08300781Server_Name\SQL08Full2011-08-24 16:25:31.00076480E:\SQLDATA\DB_Name.mdf
DB_Name598.08300781Server_Name\SQL08Full2011-08-24 16:25:31.0002E:\SQLDATA\DB_Name_1.ldf
DB_Name598.08398437Server_Name\SQL08Full2011-08-24 16:28:39.00076480E:\SQLDATA\DB_Name.mdf
DB_Name598.08398437Server_Name\SQL08Full2011-08-24 16:28:39.0006E:\SQLDATA\DB_Name_1.ldf
DB_Name598.08398437Server_Name\SQL08Full2011-08-24 20:00:11.00076480E:\SQLDATA\DB_Name.mdf
DB_Name598.08398437Server_Name\SQL08Full2011-08-24 20:00:11.0005E:\SQLDATA\DB_Name_1.ldf
DB_Name598.08398437Server_Name\SQL08Full2011-08-24 20:00:22.00076480E:\SQLDATA\DB_Name.mdf
DB_Name598.08398437Server_Name\SQL08Full2011-08-24 20:00:22.0002E:\SQLDATA\DB_Name_1.ldf
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