RESTORE hourly transaction log to every 10 min interval

Question

I have an hourly transaction log backup running for my production database. I have to implement the below scenario to check for a deleted data.

I have two tlogs.

• tlog1.trn at 10 AM
• tlog2.trn at 11 AM

I already have the recent full backup restored and differential till 09 AM restored.I want to restore tlog1.trn to every 10 minutes and copy data from a table say ,table1 to another table table2 in the same db or different db.

Using SQL Server 2016.

Is this a possible scenario?Do i have to use cursors.? I know that restore in STANDBY mode will let me read the data. Please help me how to restore to every 10 min restore point? I know that there is STOPAT option in restore command,but how can i restore to every 10 min interval.?Any syntax for that?

Answer 1

You should be able to code up a series of restore logs (with standby) and specify the STOPAT with 10 minute increments

--Full database restore with standby
USE master
GO
RESTORE DATABASE [StandbyTest]
FROM DISK = N'c:\StandbyTest\StandbyTest.bak'
WITH FILE = 1
    ,REPLACE
    ,STANDBY = N'C:\StandbyTest\ROLLBACK_UNDO_StandbyTest.BAK'
GO

--Pretend this was created at 10am
RESTORE LOG [StandbyTest]
FROM DISK = N'C:\StandbyTest\StandbyTest.trn'
WITH FILE = 1
    ,NOUNLOAD
    ,STATS = 10
    ,STANDBY = N'C:\StandbyTest\ROLLBACK_UNDO_StandbyTest.BAK'
    ,stopat = '2018-07-26 09:10:00' --10 minute interval
GO

--Copy data to another table

RESTORE LOG [StandbyTest]
FROM DISK = N'C:\StandbyTest\StandbyTest.trn'
WITH FILE = 1
    ,NOUNLOAD
    ,STATS = 10
    ,STANDBY = N'C:\StandbyTest\ROLLBACK_UNDO_StandbyTest.BAK'
    ,stopat = '2018-07-26 09:20:00'     --10 minute interval
GO

--Copy data to another table

RESTORE LOG [StandbyTest]
FROM DISK = N'C:\StandbyTest\StandbyTest.trn'
WITH FILE = 1
    ,NOUNLOAD
    ,STATS = 10
    ,STANDBY = N'C:\StandbyTest\ROLLBACK_UNDO_StandbyTest.BAK'
    ,stopat = '2018-07-26 09:30:00'     --10 minute interval
GO

--Copy data to another table

RESTORE LOG [StandbyTest]
FROM DISK = N'C:\StandbyTest\StandbyTest.trn'
WITH FILE = 1
    ,NOUNLOAD
    ,STATS = 10
    ,STANDBY = N'C:\StandbyTest\ROLLBACK_UNDO_StandbyTest.BAK'
    ,stopat = '2018-07-26 09:40:00'     --10 minute interval
GO

--Copy data to another table

RESTORE LOG [StandbyTest]
FROM DISK = N'C:\StandbyTest\StandbyTest.trn'
WITH FILE = 1
    ,NOUNLOAD
    ,STATS = 10
    ,STANDBY = N'C:\StandbyTest\ROLLBACK_UNDO_StandbyTest.BAK'
    ,stopat = '2018-07-26 09:50:00'     --10 minute interval
GO

--

Then, proceed on to your next transaction log created at 11am and repeat the restore commands, but alter the STOPAT time for each one.

Answer 2

Hi i have created the script to restore every 1 minute and then copy the data to another table in another database.

create table #GARrestorefiles(
backupsetid int
,backupstartdate datetime
,backupfinishdate datetime
,databasename varchar(100)
,backupfile VARCHAR(100)
)
insert into #GARrestorefiles (backupsetid,backupstartdate,backupfinishdate,databasename,backupfile) 
SELECT bs.backup_set_id,bs.backup_start_date,(bs.backup_finish_date),bs.database_name,
bms.physical_device_name
FROM msdb.dbo.backupset bs
INNER JOIN msdb.dbo.backupmediafamily bms
ON bs.media_set_id = bms.media_set_id
INNER JOIN master.dbo.sysdatabases s
ON bs.database_name = s.name
WHERE
s.dbid IN (5) 
AND bs.type = 'L'
--and backup_set_id = 1113
and backup_finish_date > '2018-07-27 08:45:00.000' 
--and backup_finish_date < '2018-07-25 13:00:00.000'
group by bs.database_name,bs.backup_set_id,bms.physical_device_name,bs.backup_start_date,bs.backup_finish_date
order by bs.backup_finish_date asc


DECLARE @DBfileToRestore VARCHAR(100),@Backupfinishdate datetime, @backupLocation varchar(500)
--, @mdfLocation varchar(500)
--, @ldfLocation varchar(500)

DECLARE restorecursor CURSOR FOR
SELECT backupfile,backupfinishdate FROM #GARrestorefiles

OPEN restorecursor

FETCH NEXT FROM restorecursor
INTO @DBfileToRestore,@Backupfinishdate

WHILE @@FETCH_STATUS = 0
BEGIN
    --SET @mdfLocation = 'F:\Files\Restore_Files\' + @DBfileToRestore + '.mdf'
    --SET @ldfLocation = 'F:\Files\Restore_Files\' + @DBfileToRestore + '.ldf'
--**********************************************************************************

--DECLARE @cmd nvarchar(4000)
DECLARE @srcbkpLocation nvarchar(4000)
DECLARE @destbkpLocation nvarchar(4000)
DECLARE @bkpFileName nvarchar(4000)
DECLARE @bkpFileName1 nvarchar(4000)
declare @dbname nvarchar(40)
DECLARE @date datetime;
DECLARE @Start_time datetime = DATEADD(minute,-5,@Backupfinishdate);
DECLARE @increase INT = 01;
DECLARE @STOPAT_time DATETIME = DATEADD(minute, @increase, @Start_time);
declare @backup_finish_date datetime
DECLARE @backupsetid int = 1878;

SET @backupLocation = @DBfileToRestore
SET @backup_finish_date = @Backupfinishdate
while(@STOPAT_time <= DATEADD(minute,01,@backup_finish_date))
    BEGIN
    PRINT @STOPAT_time
        RESTORE LOG AICS_QUERY_DEMO
        FROM DISK = @backupLocation
        WITH FILE = 1
        ,NOUNLOAD
        ,STATS = 10
        ,STANDBY = N'F:\SQL_Backup\AICS_Query\ROLLBACK_AICS_QUERY_DEMO.BAK'
        --,stopat = '2018-07-26 09:10:00' --10 minute interval
        ,stopat = @STOPAT_time
        SET @STOPAT_time = DATEADD(minute, @increase, @STOPAT_time);
    END
    INSERT INTO [RestoreDB].[dbo].[EmployeeDetail](Id,Name,Age,Location) 
    select Id,Name,Age,Location from [AICS_QUERY_DEMO].[dbo].[EmployeeDetail]
--Created a unique index on Id column with ignore duplicate ON to avoid duplicate entry.
--*******************************************************************************************
    FETCH NEXT FROM restorecursor
    INTO @DBfileToRestore,@Backupfinishdate
END
CLOSE restorecursor
DEALLOCATE restorecursor

I use a cursor to loop through different transaction log files and then a while loop to stopat every 1 minute and then restore a table.