Duplicate Statistics

Shaun J. Stuart discusses removing duplicate statistics:

I puzzled on this for a bit and got sidetracked by the strange way SSMS displays statistics columns on the Property page. Then it got to be the end of the day and I went home. The next day, I had a comment on my previous post from Aaron Bertrand who mentioned there is a related bug with the stats_column_id column of the sys.stats_columns view. It does not contain what the MSDN documentation says it contains. The Connect item for this, along with a workaround, can be found here.

The script I was using did not reference that column, but it did get me thinking that perhaps the script was not correctly identifying the first column in an index.

Shaun has an updated version of a duplicate statistics checker script that you may want to check out.

Related Posts

The Importance of Cardinality

Bert Wagner shows us why cardinality is important to understand when indexing data: When building indexes for your queries, the order of your index key columns matters.  SQL Server can make the most effective use of an index if the data in that index is stored in the same order as what your query requires for […]

Read More

Calculating Skew In SQL

Lukas Eder shows how you can use PERCENTILE_DISC to calculate skewness in SQL: In RDBMS, we sometimes use the term skew colloquially to mean the same thing as non-uniform distribution, i.e. a normal distribution would also be skewed. We simply mean that some values appear more often than others. Thus, I will put the term […]

Read More

Categories

August 2016
MTWTFSS
« Jul Sep »
1234567
891011121314
15161718192021
22232425262728
293031