Category Archives: SQL Server 2012

How to restart an Interrupted Database Restore in SQL Server?

Steps to restart an Interrupted Database Restore in SQL Server

There may scenario when you are restoring VLDB database backup and the restore database command interrupted due network failure, power failure, SQL Server Service restart or cluster failover. In this kind of scenario you can easily start the interrupted restore from the point of failure using WITH RESTART command.

Before you start restoring the database using WITH RESTART option check database is in Restoring State not in any other state.

You can check the database state either from SSMS object explorer or by executing below T-SQL command

select name,state_desc from sys.databases

Once confirmed that database is in restoring state execute the backup command WITH RESTART clause

RESTORE DATABASE [AdventureWorks]
FROM DISK ='D:\Backup\AdventureWorks.bak'
WITH RESTART, STATS = 20
GO

Database Backup WITH CHECKSUM

Backup WITH CHECKSUM

When WITH CHECKSUM option is used while taking backup, the backup process will verify each page for checksums and torn page. In case bad page checksum found, the backup will stop. Using backup checksums may affect workload and backup throughput.

If you want to continue the backup, you have to write CONTINUE_AFTER_ERROR in backup WITH clause.
In case backup completes successfully it means no bad checksums.

Example

backup database sqldba to disk = 'c:\jspace\sqldba1.bak'
with checksum

You can also use the 3023 trace flag for the check sum option, when 3023 trace flag is on WITH CHECKSUM option will be applied all the backups by default.

DBCC TRACEON(3023)
GO                              

backup database sqldba to disk = 'c:\jspace\sqldbatraceflag.bak'

DBCC TRACEOFF(3023)
GO                              

Let’s check if the 3023 trace flag applied the page checksum to above backup command or not. Execute below query for it.

RESTORE HEADERONLY
FROM DISK = 'c:\jspace\sqldbatraceflag.bak'
GO  

HasBackupCheckSums value is 1, it means that WITH CHECKSUM option applied to backup using 3023 trace flag.
checksum

Error Fix: Microsoft SQL Server, Error: 14516

Problem: Proxy (1) is not allowed for subsystem “SSIS” and user “Domain\UserName”. Grant permission by calling sp_grant_proxy_to_subsystem or sp_grant_login_to_proxy. (Microsoft SQL Server, Error: 14516)

Solution:
Above error occurs when the user with the minimum permission (i.e. SQLAgentReaderRole and SQLAgentUserRole) or the user is configured as job owner and trying to run the job which is running under the proxy account security context.

You can execute below script to grant permission to the user and fix the error.


EXEC dbo.sp_grant_login_to_proxy
    @login_name = 'Domain\UserName',
    @proxy_name = 'Proxy Name' ;
GO

T-SQL Script to Check the Native Compressed backup file size and Backup Compression Ratio

First of all make sure backup compression is enabled on the SQL Server. You can execute below query to check the backup compression.

select name,[description],value_in_use from sys.configurations where name like '%backup%'

Execute below script to check the compressed backup file size and backup compression ratio.

Declare @FromDate as datetime
-- Specify the from date value
set @FromDate = GETDATE() -1

SELECT  
   CONVERT(CHAR(100), SERVERPROPERTY('Servername')) AS SQLServerName, 
   msdb.dbo.backupset.database_name,  
   CASE msdb..backupset.type  
       WHEN 'D' THEN 'Database'  
       WHEN 'L' THEN 'Log'  
       WHEN 'I' THEN 'Differential'  
   END AS backup_type,  
   msdb.dbo.backupset.backup_start_date,  
   msdb.dbo.backupset.backup_finish_date, 
   msdb.dbo.backupset.expiration_date, 
   DATEDIFF (SECOND, msdb.dbo.backupset.backup_start_date, msdb.dbo.backupset.backup_finish_date) 'Backup Elapsed Time (sec)',
   msdb.dbo.backupset.compressed_backup_size AS 'Compressed Backup Size in KB',
  (msdb.dbo.backupset.compressed_backup_size/1024/1024) AS 'Compress Backup Size in MB',
   CONVERT (NUMERIC (20,3), (CONVERT (FLOAT, msdb.dbo.backupset.backup_size) /CONVERT (FLOAT, msdb.dbo.backupset.compressed_backup_size))) 'Compression Ratio',
   CASE msdb..backupset.type  
       WHEN 'D' THEN 'Database'  
       WHEN 'L' THEN 'Log'  
   END AS backup_type,  
   msdb.dbo.backupset.backup_size,  
   msdb.dbo.backupmediafamily.logical_device_name,  
   msdb.dbo.backupmediafamily.physical_device_name,   
   msdb.dbo.backupset.name AS backupset_name, 
   msdb.dbo.backupset.description 
FROM   msdb.dbo.backupmediafamily  
   INNER JOIN msdb.dbo.backupset ON msdb.dbo.backupmediafamily.media_set_id = msdb.dbo.backupset.media_set_id 
WHERE 
CONVERT(datetime, msdb.dbo.backupset.backup_start_date, 102) >= @FromDate
AND msdb.dbo.backupset.backup_size > 0 
ORDER BY  
   msdb.dbo.backupset.database_name, 
   msdb.dbo.backupset.backup_finish_date

SQL Server – Backup Verification Script – Based on conditions

Problem: There are scenarios where you have to verify the multiple SQL Server instances backup within limited time frame whether it meet your organization backup criteria standards or not.

Solution:
You can execute below T-SQL script to check the backup status as per your organization standard by assigning backup conditions value to backup criteria variable. You can execute below script either by connecting each SQL Server Instance or execute it by registering all the SQL Server Instances in Central Management Server (CMS).

Below T-SQL Script work with all the versions of MSSQL Server and verify FULL, Differential and Transaction Log Backup. It will check the max backup date and evaluate result based on condition as backup is Passed or Not.

Backup Verification Script will return below values. Column names are self-explanatory.
• SQLInstanceName
• DatabaseName
• db_create_ddate
• DB_Recovery_Model
• dbstatus
• windowsservername
• productversion
• productlevel
• edition
• current_datetime
• last_full_backup_date
• last_diff_backup_date
• last_tran_backup_date
• days_since_last_full_backup
• days_since_last_diff_backup
• hours_since_last_tranlog_backup
• Full_Backup_Stauts
• Diff_Backup_Stauts
• Log_Backup_Stauts
• full_backup_location
• diff_backup_location
• tlog_backup_location

You have to specify the backup condition based on your organization standard by assigning values to below variables.

declare @full_backup_criteria_in_days int
declare @diff_backup_criteria_in_days int
declare @log_backup_criteria_in_hours int

-- specify the backup criteria
set @full_backup_criteria_in_days = 7 -- 7 day older Full Backup is Pass 
set @diff_backup_criteria_in_days = 1 -- 1 day older Diff Backup is Pass 
set @log_backup_criteria_in_hours = 2 -- 2 hours older Log Backup is Pass

Complete Backup Verification Script

declare @full_backup_criteria_in_days int
declare @diff_backup_criteria_in_days int
declare @log_backup_criteria_in_hours int

-- specify the backup criteria
set @full_backup_criteria_in_days = 7 -- 7 day older Full Backup is Pass 
set @diff_backup_criteria_in_days = 1 -- 1 day older Diff Backup is Pass 
set @log_backup_criteria_in_hours = 2 -- 2 hours older Log Backup is Pass

select     
           serverproperty('servername') as SQLInstanceName,
           quotename(bkup_full.[database_name]) as DatabaseName,
            ( select    sdb.crdate
              from      [master]..[sysdatabases] sdb
              where     sdb.name = bkup_full.[database_name]
            ) as [db_create_ddate],           
           databasepropertyex(bkup_full.[database_name],'recovery')  as DB_Recovery_Model,
           databasepropertyex(bkup_full.[database_name],'status')  as dbstatus,       
           case serverproperty('isclustered') 
                        when 1 then cast(serverproperty('computernamephysicalnetbios') as varchar)
                        when 0 then cast(serverproperty('machinename') as varchar)
           end as windowsservername,
           serverproperty('productversion') as productversion,
           serverproperty('productlevel') as productlevel,
           serverproperty('edition') as edition,

           current_timestamp as current_datetime,
		   
		   bkup_full.[backup_finish_date] as [last_full_backup_date],           
		   bkup_diff.[backup_finish_date] as [last_diff_backup_date] ,
		   bkup_log.[backup_finish_date] as [last_tran_backup_date] ,

           datediff(dd, bkup_full.[backup_finish_date], current_timestamp) as [days_since_last_full_backup] ,
           datediff(dd, bkup_diff.[backup_finish_date], current_timestamp) as [days_since_last_diff_backup] ,
           datediff(hh, bkup_log.[backup_finish_date], current_timestamp) as [hours_since_last_tranlog_backup] ,
            
           case 
                        when datediff(dd, bkup_full.[backup_finish_date], current_timestamp) <= @full_backup_criteria_in_days  
                        then 'Pass'
                        else 'Fail'
                        end as Full_Backup_Stauts,
            
            case 
                        when datediff(dd, bkup_diff.[backup_finish_date], current_timestamp) <= @diff_backup_criteria_in_days  then 'Pass'
                        else case when quotename(bkup_full.[database_name]) IN ('[master]') then 'N/A' else 'Fail' end                        
                        end as Diff_Backup_Stauts,

            case 
                        when datediff(hh, bkup_log.[backup_finish_date], current_timestamp) <= @log_backup_criteria_in_hours  then 'Pass'
                        else case when databasepropertyex(bkup_full.[database_name],'recovery') = 'SIMPLE' then 'N/A' else 'Fail' end                        
            end as Log_Backup_Stauts,            

            ( select top 1 [physical_device_name]
              from      [msdb]..[backupmediafamily] bkup_media_family
              where     bkup_media_family.[media_set_id] = bkup_full.[media_set_id]
            ) as [full_backup_location] ,
            ( select top 1  [physical_device_name]
              from      [msdb]..[backupmediafamily] bkup_media_family
              where     bkup_media_family.[media_set_id] = bkup_diff.[media_set_id]
            ) as [diff_backup_location] ,
            ( select top 1  [physical_device_name]
              from      [msdb]..[backupmediafamily] bkup_media_family
              where     bkup_media_family.[media_set_id] = bkup_log.[media_set_id]
            ) as [tlog_backup_location]
         
                             
    from    [msdb]..[backupset] as bkup_full
            left join [msdb]..[backupset] as bkup_log on bkup_log.[database_name] = bkup_full.[database_name]
                                                       and bkup_log.[server_name] = bkup_full.[server_name]
                                                       and bkup_log.[type] = N'L'
                                                       and bkup_log.[backup_finish_date] = ( (select  max([backup_finish_date])
                                                                                            from    [msdb]..[backupset] b2
                                                                                            where   b2.[database_name] = bkup_full.[database_name]
                                                                                                    and b2.[server_name] = bkup_full.[server_name]
                                                                                                    and b2.[type] = N'L') )
            left join [msdb]..[backupset] as bkup_diff on bkup_diff.[database_name] = bkup_full.[database_name]
                                                       and bkup_diff.[server_name] = bkup_full.[server_name]
                                                       and bkup_diff.[type] = N'I'
                                                       and bkup_diff.[backup_finish_date] = ( (select max([backup_finish_date])
                                                                                            from    [msdb]..[backupset] b2
                                                                                            where   b2.[database_name] = bkup_full.[database_name]
                                                                                                    and b2.[server_name] = bkup_full.[server_name]
                                                                                                     and b2.[type] = N'I') )
    where   bkup_full.[type] = N'D'
            and bkup_full.[backup_finish_date] = ( (select  max([backup_finish_date])
                                                 from   [msdb]..[backupset] b2
                                                 where  b2.[database_name] = bkup_full.[database_name]
                                                        and b2.[server_name] = bkup_full.[server_name]
                                                        and b2.[type] = N'D') )
            and exists ( select [name]
                         from   [master]..[sysdatabases]
                         where  [name] = bkup_full.[database_name] )
            and bkup_full.[database_name] <> N'tempdb'