Monday, November 28, 2016

Backup Restore Chain re-visited, again.

(This is an update to Backup Restore Chain revisited I posted February 2016) .


In the morning hours our disk system lost the log files for all my user databases due to a firmware bug....  The connection to the disks could not be re-established and new drives was set up.  With all the databases being in Full Recovery mode, as well as having JUST completed transaction log backups a minute prior to the loss of disks, it was established that we could restore what we had with minimal loss.

However, there was many databases affected, and each would have about 45 files to restore.  I quickly pulled the query out from the previous article and the numbers from it matched what I had found just taking a quick look at the backup tables.  My previous script would just give me a list of files, in the correct order to be restored.  For a total of 450 files, this seemed like too much to manually copy and paste without messing up somewhere.  With my boss we decided it was better to spend my time rewriting my query to also give the restore statements.

All comments from previous blog posts on this subject still applies.  The script assumes a couple of things, mainly that restores are happening to the same location as they where backed up from, i.e. no WITH MOVE commands included.  This would be fairly easy to add if you need it, and I might go ahead and made another version later that does this as time permits.


The output from the procedure when called with a 2 for the output parameter looks like this:

Code is below, can also be found in my Github

set quoted_identifier off;
go
use master
go

create procedure sp_RestoreChainByDB2
@DBName sysname,
@Output int = 1, --  default to previous versions output
@MaxFullBackupDate date = NULL

as
begin
/****************
Created by @SQLSoldier
http://www.sqlsoldier.com/wp/sqlserver/day3of31daysofdisasterrecoverydeterminingfilestorestoredatabase

2015-09-24
Modified by Anders Pedersen
Twitter: @arrowdrive
Blog: Blog.AndersOnSQL.com
Made to work with SQL 2008R2.


2016-02-26
Modified by Anders Pedersen
Fix issue where First_LSN and Last_LSN values are the same on a record for the trasaction log backups.
These transaction log backups can be ignored in the restore chain.
Also made into a procedure, with the database name for a required parameter, and max date for the full backup to start with as a parameter

2016-11-28
Modified by Anders Pedersen
Added support for scripting out restore statements.
Added parameter @output for what the script should print out: 1 = Restore chain only, 2 = Restore Script only, 3 = both

Note that the restore scripts assume the files are going back to the original location.
This part could easily be modified by adding parameters for data and log file location
Or even made table driven if a lot of files going to different locations.
This was made for my own need to quickly create a restore chain to recover a server where the databases existed, but had to be over written.
*****************/
Declare @DBBackupLSN numeric(25, 0)

Declare @Baks Table (
BakID int identity(1, 1) not null primary key,
backup_set_id int not null,
media_set_id int not null,
first_family_number tinyint not null,
last_family_number tinyint not null,
first_lsn numeric(25, 0) null,
last_lsn numeric(25, 0) null,
database_backup_lsn numeric(25, 0) null,
backup_finish_date datetime null,
type char(1) null,
family_sequence_number tinyint not null,
physical_device_name nvarchar(260) not null,
device_type tinyint null,
checkpoint_LSN numeric (25,0)-- Anders 2015-09-24
)
Set NoCount On;



-- Get the most recent full backup with all backup files
Insert Into @Baks (backup_set_id,
media_set_id,
first_family_number,
last_family_number,
first_lsn,
last_lsn,
database_backup_lsn,
backup_finish_date,
type,
family_sequence_number,
physical_device_name,
device_type
,checkpoint_LSN)-- Anders
Select Top(1) With Ties B.backup_set_id,
B.media_set_id,
B.first_family_number,
B.last_family_number,
B.first_lsn,
B.last_lsn,
B.database_backup_lsn,
B.backup_finish_date,
B.type,
BF.family_sequence_number,
BF.physical_device_name,
BF.device_type
, B.checkpoint_lsn -- Anders 2015-09-24
From msdb.dbo.backupset As B
Inner Join msdb.dbo.backupmediafamily As BF
On BF.media_set_id = B.media_set_id
And BF.family_sequence_number Between B.first_family_number And B.last_family_number
Where B.database_name = @DBName
And B.is_copy_only = 0
And B.type = 'D'
And BF.physical_device_name Not In ('Nul', 'Nul:')
and convert(DATE,B.backup_start_date) <=(CASE
when @MaxFullBackupDate is not null then   @MaxFullBackupDate
else convert(DATE,B.backup_start_date) end) -- Anders 2016-02-26

Order By backup_finish_date desc, backup_set_id;


-- Get the lsn that the differential backups, if any, will be based on
Select @DBBackupLSN = checkpoint_LSN -- Anders 2015-09-24
From @Baks;

-- Get the most recent differential backup based on that full backup
Insert Into @Baks (backup_set_id,
media_set_id,
first_family_number,
last_family_number,
first_lsn,
last_lsn,
database_backup_lsn,
backup_finish_date,
type,
family_sequence_number,
physical_device_name,
device_type)
Select Top(1) With Ties B.backup_set_id,
B.media_set_id,
B.first_family_number,
B.last_family_number,
B.first_lsn,
B.last_lsn,
B.database_backup_lsn,
B.backup_finish_date,
B.type,
BF.family_sequence_number,
BF.physical_device_name,
BF.device_type
From msdb.dbo.backupset As B
Inner Join msdb.dbo.backupmediafamily As BF
On BF.media_set_id = B.media_set_id
And BF.family_sequence_number Between B.first_family_number And B.last_family_number
Where B.database_name = @DBName
And B.is_copy_only = 0
And B.type = 'I'
And BF.physical_device_name Not In ('Nul', 'Nul:')
And B.database_backup_lsn = @DBBackupLSN

Order By backup_finish_date Desc, backup_set_id;


--select * from @Baks

-- Get the last LSN included in the differential backup,
-- if one was found, or of the full backup
Select Top 1 @DBBackupLSN = last_lsn
From @Baks
Where type In ('D', 'I')
Order By BakID Desc;

-- Get first log backup, if any, for restore, where
-- last_lsn of previous backup is >= first_lsn of the
-- log backup and <= the last_lsn of the log backup
Insert Into @Baks (backup_set_id,
media_set_id,
first_family_number,
last_family_number,
first_lsn,
last_lsn,
database_backup_lsn,
backup_finish_date,
type,
family_sequence_number,
physical_device_name,
device_type)
Select Top(1) With Ties B.backup_set_id,
B.media_set_id,
B.first_family_number,
B.last_family_number,
B.first_lsn,
B.last_lsn,
B.database_backup_lsn,
B.backup_finish_date,
B.type,
BF.family_sequence_number,
BF.physical_device_name,
BF.device_type
From msdb.dbo.backupset B
Inner Join msdb.dbo.backupmediafamily As BF
On BF.media_set_id = B.media_set_id
And BF.family_sequence_number Between B.first_family_number And B.last_family_number
Where B.database_name = @DBName
And B.is_copy_only = 0
And B.type = 'L'
And BF.physical_device_name Not In ('Nul', 'Nul:')
And @DBBackupLSN Between B.first_lsn And B.last_lsn
Order By backup_finish_date, backup_set_id;

-- Get last_lsn of the first log backup that will be restored
Set @DBBackupLSN = Null;
Select @DBBackupLSN = Max(last_lsn)
From @Baks
Where type = 'L';


--select * from @Baks;

-- Recursively get all log backups, in order, to be restored
-- first_lsn of the log backup = last_lsn of the previous log backup
With Logs
As (Select B.backup_set_id,
B.media_set_id,
B.first_family_number,
B.last_family_number,
B.first_lsn,
B.last_lsn,
B.database_backup_lsn,
B.backup_finish_date,
B.type,
BF.family_sequence_number,
BF.physical_device_name,
BF.device_type,
1 As LogLevel
From msdb.dbo.backupset B
Inner Join msdb.dbo.backupmediafamily As BF
On BF.media_set_id = B.media_set_id
And BF.family_sequence_number Between B.first_family_number And B.last_family_number
Where B.database_name = @DBName
And B.is_copy_only = 0
And B.type = 'L'
And BF.physical_device_name Not In ('Nul', 'Nul:')
And B.first_lsn = @DBBackupLSN
and B.First_lsn <> B.Last_Lsn -- Anders 2016-02-26
Union All
Select B.backup_set_id,
B.media_set_id,
B.first_family_number,
B.last_family_number,
B.first_lsn,
B.last_lsn,
B.database_backup_lsn,
B.backup_finish_date,
B.type,
BF.family_sequence_number,
BF.physical_device_name,
BF.device_type,
L.LogLevel + 1
From msdb.dbo.backupset B
Inner Join msdb.dbo.backupmediafamily As BF
On BF.media_set_id = B.media_set_id
And BF.family_sequence_number Between B.first_family_number And B.last_family_number
Inner Join Logs L On L.database_backup_lsn = B.database_backup_lsn
Where B.database_name = @DBName
And B.is_copy_only = 0
And B.type = 'L'
And BF.physical_device_name Not In ('Nul', 'Nul:')
And B.first_lsn = L.last_lsn
and B.First_lsn <> B.Last_Lsn) -- Anders 2016-02-26
Insert Into @Baks (backup_set_id,
media_set_id,
first_family_number,
last_family_number,
first_lsn,
last_lsn,
database_backup_lsn,
backup_finish_date,
type,
family_sequence_number,
physical_device_name,
device_type)
Select backup_set_id,
media_set_id,
first_family_number,
last_family_number,
first_lsn,
last_lsn,
database_backup_lsn,
backup_finish_date,
type,
family_sequence_number,
physical_device_name,
device_type
From Logs
Option(MaxRecursion 0);

-- Select out just the columns needed to script restore
IF OBJECT_ID('tempdb..#Baks') IS NOT NULL
DROP TABLE #Baks

Select RestoreOrder = Row_Number() Over(Partition By family_sequence_number Order By BakID),
RestoreType = Case When type In ('D', 'I') Then 'Database'
When type = 'L' Then 'Log'
End,
DeviceType = Case When device_type in (2, 102) Then 'Disk'
When device_type in (5, 105) Then 'Tape'
End,
PhysicalFileName =  replace (physical_device_name, '\\agdata.int\backups\ebusiness\eBiz\MONSANTO\MONSANTO', '\\BU\AndersTest\AndersTest')
into #Baks -- to stop from having to read it twice, this could be done neater
From @Baks
Order By BakID;

Set NoCount on;
set quoted_identifier off;

if @Output in (1,3)
select * from #Baks

if @Output in (2,3)
begin
/****
Anders 2016-11/28
This could be done going into a temp table to create one output, but that would create a column name
Done this way, the script can simply be copied and pasted to a new query window to be executed
*****/


select "restore database " + @DBName +" from DISK = '" + PhysicalFileName + "' with NORECOVERY" + case when RIGHT(PhysicalFileName, 3) = 'bak' then " , REPLACE" else "" end
from #Baks
where RestoreType = 'Database'
order by RestoreOrder



select  "restore log " + @DBName +" from DISK = '" + PhysicalFileName + "' with NORECOVERY"
from #Baks
where RestoreType = 'Log'
order by RestoreOrder

-- recover the database
select "RESTORE DATABASE " +@DBName + " WITH RECOVERY"
end


Set NoCount Off;

END -- proc




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