Accurate statistics about the data held in tables are used to provide the best execution strategy for SQL queries. but if the statistics don't accurately reflect the current contents of the table you'll get a poorly-performing query. How do you find out if statistics are correct, and what can you do if the automatic update of statistics isn't right for the way a table is used?
2013-04-15
6,631 reads
If you need to optimise SQL Server performance, it pays to understand SQL Server Statistics. Grant Fritchey answers some frequently-asked questions about SQL Server Statistics: the ones we somehow feel silly asking in public, and think twice about doing so.
2013-03-12
3,545 reads
If you need to optimise SQL Server performance, it pays to understand SQL Server Statistics. Grant Fritchey answers some frequently-asked questions about SQL Server Statistics: the ones we somehow feel silly asking in public, and think twice about doing so.
2013-03-01
4,125 reads
2012-11-06
1,950 reads
2012-10-09
2,498 reads
How can I find out which statistics are outdated in my SQL Server database?
2012-09-06
3,505 reads
2011-09-23
2,479 reads
It comes as rather a shock to find out that one of the commonest circumstances in an OLTP database, an ascending primary key with most querying on the latest records, can throw the judgement of the Query Optimiser to the extent that perfomance nose-dives. Fabiano Amorim once again dons snorkel and goggles to explore the murky depths of execution plans to find out why.
2011-09-16
2,528 reads
SQL Server Statistics assist the query optimiser to calculate the best way of running the query. Holger describes every common way that things can go wrong with statistics, and how to put matters right.
2010-11-11
3,714 reads
2010-04-16
3,727 reads
Continuing with my takeaways from SQLCon and FabCon Europe in Barcelona, let’s talk about...
By Steve Jones
Next year the PASS Data Community Summit is in DENVER! and London, but Denver...
By Steve Jones
Yesterday was the first day of sessions at the PASS Data Community Summit (after...
Comments posted to this topic are about the item Pay for Performance, which is...
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Comments posted to this topic are about the item Enforcing Unique Customer Emails When...
I run this query:
SELECT s.name AS schemaname , o.name AS objectname FROM sys.objects o INNER JOIN sys.schemas s ON s.schema_id = o.schema_id WHERE o.name = 'Beer'I get one row back for an object named dbo.beer. There is an ETL schema and both of these are nonpartitioned tables. I run this code:
ALTER TABLE dbo.beer switch TO etl.beerWhat happens? See possible answers