Backup And Restore With Move

John Morehouse has a script for database migration onto a differently configured server:

Now, not every environment is the same.  Instances get configured differently or things change just due to the nature of the business.  In a previous life I would routinely have to backup a database and restore it to another server.  However, the server I was using to restore to had a different drive configuration.  It happens.  Anyway, I wanted a script that would give me

  • A backup statement
  • A restore statement with the appropriate MOVE switch

This would allow me to easily execute the backup statement and then on the target server execute the restore statement.  Since the restore statement already had the appropriate MOVE switch provided, I didn’t have to manually compose the statement.

Click through for the script.

Backup Management Is More Than Taking Backups

Kenneth Fisher makes a great point regarding backups:

I’ve said before that backups are at once one of the easiest things DBAs do, one of the most important, and one of the most complicated. Take a full backup, restore it. Pretty simple right? And yet it’s vital when accident or corruption require recovering data. And as simple as it can be on the surface, the more you dig, the more there is to know, and the more complicated it can become. Well, one of those complications is the backup of the backup files. I mean, assuming you are using native backups, that full backup is sitting on a drive somewhere, and hopefully, that drive gets backed up right?

Why? Well, for performance purposes you probably back up your databases locally. To a drive attached to the server. Now you may not, heck you could be backing up to Azure, but for the sake of this argument let’s say you are. Part of a careful disaster recovery plan is making sure you have access to those backups. I’ve heard stories of entire data centers going underwater (literally). You need to at least have a copy of your backups in a separate system, separate location from production.

The proliferation of S3/Blob Storage for “warm” backups and Glacier/Cool Blob Storage for “cold” backups has made it much cheaper to retain longer-term backups.

The SQL Server Backup Survey

Mike Fal ran a survey recently and shares his findings:

This leads me to last week. In order to have some data, I decided to run an informal backup survey targeted at the SQL community. The results floored me: 344 of you decided to take my short survey. This really helps me understand some of the trends out there and now I want to share those results with you.

Before I get started, I want to first thank each and every person who responded from the bottom of my heart. This data is the result of your participation. Secondly, I want to underscore the “informal” nature of this. There’s a lot of holes that can probably be poked in the process, but I think the data is still useful and can give people insight into the trends.

I’ve posted raw data along with a few tools out on GitHub, where you are welcome to download and play with it.

Check out Mike’s findings and then dig into the data on GitHub.

SQL Server Backups On Azure VM

Rolf Tesmer shows us various options available for backing up SQL Server on Azure VMs:

Recently I had a requirement to collate and briefly compare some of the various methods to perform SQL Server backup for databases deployed onto Azure IaaS machines.  The purpose was to provide a few options to cater for the different types(OLTP, DW, etc) and sizes (small to big) of databases that could be deployed there.

Up front, I am NOT saying that these are the ONLY options to perform standard SQL backups!  I am sure there are others – however – the below are both supported and well documented – which when it comes to something as critical as backups is pretty important.

So the purpose of this blog is to provide a quick and brief list of various SQL backup methods!

Read on for the options.

Smart Differential Backups

Tracy Boggiano continues her smart backups series, this time looking at differential backups:

SQL Server 2017 introduced a new column for taking smarter backups for differential backups as part of the community-driven enhancements. A new column modified_extent_page_count is introduced in sys.dm_db_file_space_usage to track differential changes in each database file of the database.  The blog referenced states it takes just as many resources to take a differential backup as a full when there are between 70% and 80% of pages changes. With this field and the allocated_extent_page_count field, we can calculate the percentage of pages changed since the last full backup. So I have added logic into the differential backups that I use in combination with the configuration tables from my Github repository.  To support this change we will be adding two new fields to the DatabaseBackupConfig table:

  • SmartBackup
  • DiffChangePercent

The main part of the code determines if you are running SQL Server 2017 then determine which databases the percentage is greater than or equal to the value you put in the table.  Then it puts in two separate variables which databases to take full backups of and which ones to take differential backups of.

Click through for the script.

SQL Server Backups To Azure Blob Storage

Kevin Hill shows  how to configure SQL Server to back up a database to Azure blob storage:

Note the “no blobs found” in the container.  After a successful backup, you will see it here.

Click on ‘Container Properties’ to get the URL for this specific container…this will be used in Backup and Restore statements.  Click the button next to the URL to copy it.  For now just remember where this is or copy it to Notepad, Query window etc.  When we start to build our T-SQL statements, we will need both the Access key from earlier and the URL.

Kevin gives clear, step by step instructions on the process.

VSS Snapshot: Freeze & Thaw

Erik Darling points out that VSS backups aren’t instantaneous and can block queries:

Ah, backups. Why are they so tough to get right?

You start taking them, you find out you’re not taking enough of them, or that they’re not the right kind, or that you’re not using checksums or compression, or that you’re not storing them in the right place, or that the storage isn’t redundant.

It’s just like, why won’t someone make this easy?

Then you read about VSS Snaps, and they look so dead simple. You don’t need your DBA Ph.D to use them.

And look how fast they are! Oh how they blaze.

Read the whole thing.

Smart Transaction Log Backups

Tracy Boggiano has started a new series on smart transaction log backups.  Part one involves taking smarter transaction log backups in SQL Server 2017:

SQL Server 2017 introduced two fields to help with taking smart backups.  One was for taking smarter log backups, for this have DMV sys.dm_db_log_stats that have two fields log_backup_time and log_since_last_backup_mb.  With the combination of these two fields, we can put some logic in the jobs that I use for Ola’s scripts that use my config tables from my Github repository.  To support this change we will be added three new fields to the DatabaseBackupConfig table:

  • SmartBackup

  • LogBackupTimeThresholdMin

  • LogBackupSizeThresholdMB

Click through for scripts.

Backups And Distributed File Shares

Wayne Sheffield ran into a new oddity recently:

I was working on a client’s site today, setting up database backup routines. Part of which is to perform a database backup, and verify that everything went okay. I had Windows Explorer open to the location that the backup was going to. When the backup finished, I navigated over to Windows Explorer… and I have a missing database backup. There wasn’t a file in the directory for the backup that I had just performed.

After double and triple checking that I was looking at the same path that I had backed up the database to, I went in search of the network sysadmin to help me figure it out.

Read on for the solution.

Additional Restore-DbaDatabase Functionality

Stuart Moore shows off a few examples of advanced Restore-DbaDatabase usage:

No matter how hard the dbatools; team tries, there’s always someone who wants to do things we’d never thought. This is one of the great things with getting feedback direct from a great community. Unfortunately a lot of these ideas are either too niche to implement, or would be a lot of complex code for a single use case.

As part of the Restore-DbaDatabase stack rewrite, I wanted to do make things easier for users to be able to get their hands dirty within the Restore stack. Not necessarily needing to dive into the core code and the world of GitHub Pull Requests, but by manipulating the data flowing through the pipeline using standard PowerShell techniques, all the while being able to do the heavy lifting without code.

Click through for several examples.


March 2018
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