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COLUMNSTORE batch mode


#1

anyone plan to write a blog about this? i had some findings about this

  1. cost of threshold for parallelism and max dop will affect the query to turn batch mode into row mode
  2. insert into table variable will turn batch mode into row mode

still in progress to find more causes.


#2

Its all a bit Brand New for an old codger like me ... but I would like to learn more.


#3

The best series I've found on Columnstore is Niko's:

If the answer isn't in there, you can contact him with a specific question. If you're on Twitter, try the #sqlhelp hashtag too.


#4

niko blog is still in my reference since 3 months ago....but he/she is more toward what is columnstore but not batch(http://www.nikoport.com/batch-mode/).

additional findings
3. record <1m rows is forever in row mode.


#5

partition elimination somehow eliminate batch mode as well.


#6

No idea if it adds anything but I stumbled over this relatively recent (28-Aug-2015) article on SQLMag
http://sqlmag.com/sql-server-2014/essential-guide-sql-server-2014-clustered-columnstore-index