2011-09-23
2,463 reads
2011-09-23
2,463 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
3,717 reads
Fabiano launches into a sound technical explanation of the way that the query optimiser works in SQL Server with a mention of Brazilian Soccer stars and young ladies on Copacabana beach. You'll never quite think of statistics, execution plans, and the query optimiser the same way again after reading this, but we think you'll understand them better.
2010-02-02
5,853 reads
With SQL Server 2005 DMVs, we can easily find query performance statistics. Every DBA has a favorite script to find query performance stats. I also have one. But, are all the queries captured by the DMVs? In this tip I will walk through capturing some of this data and show what is capture and what is not captured by the DMVs.
2009-10-05
4,784 reads
2009-09-21
3,779 reads
2009-09-17
3,601 reads
In this three-part series I'll look at what you can do to persist this data so you don't find yourself waiting for usage stats to compile over a reasonable period of time just so you can harness the power of the indexing DMOs in your performance tuning process.
2009-05-26
1,438 reads
By DataOnWheels
Picture this, your data ingestion team has created a table that has the sales...
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I've inherited a couple of rather large databases from my ex-colleague when I join...
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I have marked a few transactions in my code. How can I find out which marks were stored in a transaction log?
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