Uninstalling CUs/Downgrading SQL Server in Linux(RHEL7)

Back in 2011 I wrote an article on how to uninstall service packs in version SQL 2008/R2 which was quite a popular post at that time based on my wordpress stats. (Well, SQL 2008 was the very first version that allowed us to do that) Fast forward to year 2020 where we can have SQL Server running on Linux in production environments, let’s see how to achieve the same if you ever want to uninstall a cumulative update. Did you notice, I said CU, not service packs this time. See this post for more info on MSM.

First thing first, let’s see what we have got on the box. Pulling that information is quite simple, Run “sudo yum info mssql-server” which should return something like this.

Of course you can get this info from SQL or several other ways in Linux. Okay, now we know we got SQL Server 2019 CU5 running on this server to work with. Let’s just assume CU5 broke something in my database and I want to go back to CU4. How do I do that?

Run “sudo yum downgrade mssql-server-<your_desired_version_number>.x86_64“. Okay, so how do I get those version number details? Microsoft has those details maintained and updated regularly in their release notes. Check below links for 2019 or 2017 based on your version.
SQL 2019 release notes.
SQL 2017 release notes.

Also, We can get this information directly using YUM super powers as shown below…
sudo yum list mssql-server –showduplicates

If you want additional details for individual packages as shown below, just replace “list” with “info”, the command would be “sudo yum info mssql-server –showduplicates

Now that we have all the information what we need, let’s go to the actual fun part.

Downgrading from SQL 2019 Cu5 to CU4:
Command:
sudo yum downgrade mssql-server-15.0.4033.1-2.x86_64

As you can see it clearly states that CU5 was removed and CU4 was downloaded and installed successfully 🙂

BTW, the basic golden rule still remains the same,  you can’t downgrade to a lower version(from SQL 2019 to 2017, –> Nope, that’s not how downgrade works)! You are allowed to do whatever you want as long as you are staying at same version.

SQL Server 2016 SP2 got released :)

Microsoft released SQL Server 2016 Service Pack 2 today. Visit https://support.microsoft.com/en-us/help/4052908/sql-server-2016-service-pack-2-release-information for all the details you need. There’s a looooong list of number of bugs fixed and enhancements made. Couple of DMVs and features from SQL 2017 were back ported as well.

Make sure you go all the way to the bottom of the page regarding GOTCHAS with uninstalling 2016 SP2 if needed. This is the section which I would like you guys to focus on if you are not on Enterprise Edition.

Cheers!

SQL Server 2012 SP2 RTM got released :)

Yesterday, microsoft released Service Pack 2 for SQL Sever 2012. They made Slipstream Installation packages available as well to the customers 🙂

And hey, you know what….CU1 for SQL Server 2012 SP2 is scheduled to release in July 2014. It’s time to upgrade all your SQL Server 2012 Instances to SP2!

SP2 can be downloaded from http://www.microsoft.com/en-us/download/details.aspx?id=43340

For the list of bugs which are fixed in this Sevice pack, visit http://support.microsoft.com/kb/2958429

Couple of very critical bugs which got fixed: ( they are critical to me, YMMV) 

SQL Server crashes when LDF file for Tempdb is full.
Rollback causes SQL Server Database to go to Suspect mode.
No error message when Log backup fails in SQL Server 2012.

Cheers!

The Wait is Over-Much awaited SQL Server Service packs are just around the corner.

Hurray…! At laaaaaast Microsoft officially announced today that they are planning to ship one last Service pack for both SQL Server 2008 and 2008R2. Timing of the release will be little odd though. They will be available to public after July 8th 2014(After Mainstream support ends). This is defenitely a good news (In fact great news)  for companies which don’t let DBA’s to Install CU’s and just rely on Service Packs.

If you are curious, SQL Server 2008 SP3 was released back in 2011 October and 2008R2 SP2 was released in July 2012. Since then microsoft is releasing Cumulative updates.
Get ready for SQL Server 2008 SP4 and SQL Server 2008R2 SP3 folks  🙂

See this blog post from SQL Server Team for more information.