Cumulative Updates Every 2 Months

The SQL Server team is implementing an Incremental Servicing Model (ISM) to deliver updates for SQL Server. This is basically a fancy way of saying: Cumulative Updates (CUs) will no longer be shipped when the team feel it’s required, instead a new CU will ship every 2 months.

This scheduled approach will probably make more of a difference to the SQL Server Team than it will to sysadmins and DBAs, but it may be good news to companies who have set schedules for patching which could be aligned to match. In reality, I don’t see this model making much of a difference to us in the field, especially when you look at the rate of CU releases for SQL Server 2014 since release. Hint: it’s been every 2 months.

What’s that? You only install Service Packs and only then after the first CU for the SP has been released? Well here are some of the titles for recent bug fixes to give you nightmares.

Cumulative update 6 for SQL Server 2014:

Estimated number of rows is calculated incorrectly for a predicate involving a unique GUID column in SQL Server 2014

Column data may be deleted when you update another column in a table in SQL Server 2012 or SQL Server 2014

The CHANGETABLE function in a query returns incorrect results if change tracking is enabled for a SQL Server database

Assertion failure on secondary replica when you use AlwaysOn Availability Groups in SQL Server 2014

SELECT INTO statement together with the TABLOCKX hint or the TABLOCK and UPDLOCK hints fail on SQL Server 2014

Error occurs when you try to drop or delete filegroups or partition schemes and functions in SQL Server

Access violation when you execute a stored procedure that uses a cursor on a table variable in SQL Server

Columnstore index corruption occurs when you use AlwaysOn Availability Groups in SQL Server 2014

FileTables in an AlwaysOn availability group become unavailable after failover in an instance of SQL Server 2014

SELECT…INTO statement retrieves incorrect result from a clustered columnstore index in SQL Server 2014

So we have SQL Server deleting the wrong data, returning incorrect results from queries and introducing corruption. These are just the highlights from one CU. Do you really want to take the risk with your systems?

CUs aren’t all doom and gloom though, they often bring us new features:

Running multiple UPDATE STATISTICS for different statistics on a single table concurrently is available

An update to enable the “-k” startup parameter to control the rate that work files can spill to tempdb is available for SQL Server 2012 Service Pack 3

Update improves the Service Broker when you send messages to remote servers in SQL Server 2012 and SQL Server 2014

Further details of the new ISM plan can be found here that include information on requesting hot fixes from Microsoft. For the latest information on all updates for SQL Server versions since 2005, try Brent Ozar’s

About the author

James Anderson

I'm a freelance SQL Server DBA in Southampton, UK. Performance tuning code and improving development processes are what I love to do for work. Outside of work, I live to travel to as many places as possible with my wife Sarah.

Leave a Reply

Your email address will not be published. Required fields are marked *

Sign Up

James Anderson SQL Server DBA

Hi, I'm James Anderson. When I'm not blogging about SQL Server, I do this.

The SQL People

DBA Stackexchange Profile