Update Statistics for a partition

Last week, I was working with a client and we wanted to update statistics on a partition. After trying it out, then consulting with BOL and finally twitter, I determined that it could not be done. Thanks to Lara Rubbelke for her help and pointing out the second issue that is discussed below.

In addition to that problem, when a partition’s index is defragmented, statistics are not updated. I suppose an easy workaround is to update statistics, but the problem is that it updates statistics for all of the partitions and/or indexes of that object, not the specific one that was just defragmented.

So, I created a suggestion @connect.microsoft.com. I’ll post the entire subject / issue below, but please visit the site, vote and validate this request.

This is an https:// link, so if you aren’t logged into connect it will not work. That said, if you don’t have a login for this site, I’d recommend that you get one. Tons of great information can be found there. If you wish to search for it, go to connect.microsoft.com and type in “Update Statistics at the partition level” OR search for feedbackid 468517.  https://connect.microsoft.com/SQLServer/feedback/ViewFeedback.aspx?FeedbackID=468517

Full description and proposed solution below:

I’d like to see Update Statistics modified to include partitionID in combination with the existing table or indexed view name.

With the improvements of 2k8 and partitioning, very large result sets are being seen at one of my clients that utilizes partitioning. Having to update statistics against partitions that haven’t changed in order to achieve the change on the partition that actually needs it, creates additional overhead that is not required. It also forces a change to plans that wouldn’t otherwise be altered which causes for memory churn in the proc cache.

One other related note is that you can defrag an individual partition index, but it will not update the statistics.

Proposed Solution
Two parts:
Modify Update Statistics to include an option for declaring either a partition name or partitionID for either a table or an indexed view.
UPDATE STATISTICS table_or_indexed_view_name
{ index_or_statistics__name }
{ index_or_statistics_name }
| ( { Partition_index_or_partition_statistics_name } [ ,…n ] )
2.) Upon completion of the defrag of an individual partition index have it update the statistics for that partition.

Improved Reliability
Improved Administration
Improved Performance

  1. No trackbacks yet.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: