Roll Logs – Backup Recovery


Rolling log files for a day, especially with 15 or even 5 minute log backups is a pain at best. Here’s a slightly better way to do it. Set the two variables at the top to the directory where the log backups are and the database you’re looking to restore. It will, assuming you named your log backups as DatabaseName_Log*, display all log backups in that folder in chronological order into an output script which is best read when doing results to text (Query/Results To/Results To Text).

Here’s what this won’t do. It won’t require SQL Server to remember taking the backups, so you can run it from any server that has access to this folder. It won’t restore anything for you, it will just give you the text to copy/paste and run yourself. It won’t leave xp_cmdshell on, although it does require it to be turned on for a bit if it was off.

Since this does nothing more than display the code you’ll probably run next, feel free to run it even if you’re just playing around or only want to roll half the logs.

DECLARE @LogBackupDirectory VarChar(1000)
DECLARE @DatabaseName VarChar(256)

SELECT @LogBackupDirectory = '\\BUServer\BUShare\Folder\logs\'
    , @DatabaseName = 'model'

---Don't change anything below this point unless upgrading the script---
---Also, slight change if backup and restore database names are different---

SET NOCOUNT ON

DECLARE @XP_CmdShell_Enabled INT
    , @XP_CmdShell_Command VarChar(4000)

IF Object_ID('TempDB..#temp') IS NOT NULL BEGIN
    DROP TABLE #temp
END

create table #temp
(
      Dir VARCHAR(MAX)
)

SELECT @XP_CmdShell_Enabled = CONVERT(INT, ISNULL(value, value_in_use))
FROM master.sys.configurations
WHERE name = 'xp_cmdshell'

IF @XP_CmdShell_Enabled = 0 BEGIN
    EXEC sp_configure 'xp_cmdshell', 1
    RECONFIGURE WITH OVERRIDE 
END 

SELECT @XP_CmdShell_Command = 'dir  /od /b ' + @LogBackupDirectory + @DatabaseName + '_log*'

INSERT INTO #temp
EXECUTE xp_cmdshell @XP_CmdShell_Command

IF @XP_CmdShell_Enabled = 0 BEGIN
    EXEC sp_configure 'xp_cmdshell', 0
    RECONFIGURE WITH OVERRIDE 
END 

DELETE #temp
WHERE Dir IS NULL

SELECT commands = 'Restore Log [' + @DatabaseName + '] from DISK=N''' + @LogBackupDirectory + Dir + ''' with NoRecovery' 
FROM #temp

SELECT 'RESTORE DATABASE [' + @DatabaseName + '] WITH RECOVERY'

Backup History


Can you tell me the drive we were backing up server #58 to exactly 8 months ago, and, if possible, it would really help if you could give me the exact file name for me to pull the backup from tape for you.  Or, last night’s backup didn’t finish until after the tapes started, did those backups always take that long and is it taking longer because the databases are actually growing that much?

The answer to those questions tends to be “Ok, no problem.”

SELECT TOP 100 bs.database_name
    , bs.backup_start_date
    , bs.backup_finish_date
    , backup_duration_minutes = (DateDiff(second, backup_start_date, backup_finish_date)+30)/60
    , backup_duration_seconds = DateDiff(second, backup_start_date, backup_finish_date)
    , backup_size_mb = Cast(bs.backup_size / 1024 / 1024 as Int)
    --, compressed_backup_size_mb = Cast(bs.compressed_backup_size / 1024 / 1024 as Int) --SQL 2008+ only
    , backup_type = CASE bs.type 
                        WHEN 'D' THEN 'FULL' 
                        WHEN 'I' THEN 'Diff' 
                        WHEN 'L' THEN 'Log' 
                        ELSE 'UNKNOWN' 
                    END
    , bmf.physical_device_name
FROM msdb..backupset bs
    INNER JOIN msdb..backupmediafamily bmf ON bs.media_set_id = bmf.media_set_id
--WHERE bs.database_name like 'msdb'
    --AND bs.type <> 'L'
    --AND backup_start_date BETWEEN '2013-05-13 00:00' AND '2013-05-13 08:00'
ORDER BY Backup_Start_Date DESC

It’s common in my scripts for me to put 10 things in the where clause and comment them out. My problem is that I don’t want to look around for field names to filter my scripts, but I don’t always want to filter my scripts the same way. It works for me, and you’ll either get used to it or rewrite it for your own use.