Minimal Logging With Columnstore

Niko Neugebauer continues his columnstore series by looking at columnstore insert logging in SQL Server 2016 versus 2014:

Ladies and gentlemen! That’s quite a difference to SQL Server 2014!
We better check the total length of the transaction log to see the final result: 384.032 bytes! Ok, that is significantly more than for the rowstore heap table for sure, but what about the comparison to the SQL Server 2014 ? Did this minimal logging bring any improvement ?
Well … 🙂
In SQL Server 2014 we had 1.255.224 bytes spent on the transaction log – meaning over 1.2 MB, meaning around 3 times more, for the Delta-Store insertion! For such a simple table, this is a huge improvement, but let’s take a look at the total length of the transaction log entries in both environments (SQL Server 2014 & SQL Server 2016)

This is worth a careful read.  If you’ve spent time working with 2014 clustered columnstore indexes, there are a few changes which might affect you.  The most interesting thing for me was that the deltastore is no longer page compressed.

Related Posts

Preventing Issues With Columnstore Indexes

Kevin Chant has a post covering issues in his experience with the creation of columnstore indexes: Error due to online statement It’s a very common error caused usually by somebody copying a rowstore “Create Index” command. The “online=on” option you use with rowstore indexes does not work with creating columnstore indexes yet. For the record the […]

Read More

Avoid Key Lookups On Clustered Columnstore Indexes

Joey D’Antoni points out a potential big performance problem with clustered columnstore indexes: In the last year or so, with a large customer who makes fairly heavy use of this pattern, I’ve noticed another concern. Sometimes, and I can’t figure out what exactly triggers it, the execution plan generated, will do a seek against the […]

Read More

Categories

October 2016
MTWTFSS
« Sep Nov »
 12
3456789
10111213141516
17181920212223
24252627282930
31