SQL Server with Mr. Denny:

Index Seek

1

August 7, 2013  2:00 PM

Back To Basics: Statistics



Posted by: Denny Cherry
Back To Basics, Index Performance, Index Scan, Index Seek, Indexing, SQL Server, Statistics

Statistics are magical little objects within the database engine that have the ability to make your queries run fast or painfully slow.  The...

May 28, 2013  4:27 PM

Extra Bytes Per Row With AlwaysOn Availability Groups



Posted by: Denny Cherry
AlwaysOn, Database Administration, Execution Plans, Index, Index Performance, Index Seek, Indexing, SQL Server, SQL Server 2012

One of things to keep in mind with SQL Server 2012 AlwaysOn Availability Groups is that when the availability group has readable secondary replicas any...


April 25, 2011  2:00 PM

We get many warnings in our SQL error log about I/O requests taking longer than 15 seconds to complete. What do we do in such scenario?



Posted by: Denny Cherry
Index, Index Scan, Index Seek, SQL Server, Storage

There are a few things which you will want to look at.  First make sure that you have enough RAM for the database to use.  Without enough RAM in the SQL Server you’ll begin putting extra load on the disks because the same data is being pulled into the buffer cache from the disk over and...


September 17, 2009  11:00 AM

Dates can easily be the hardest datatype to work with.



Posted by: Denny Cherry
Index Performance, Index Scan, Index Seek, Indexing, T/SQL

The datetime data type can be one of the hardest to work with when it comes to index optimization.  Most queries that use a datetime data type for filtering (part of the where clause) only want to match the date portion of the value.  Most people handle this via a convert function around the date...


November 24, 2008  1:00 PM

Back To Basics: What’s the difference between a Scan and a Seek?



Posted by: Denny Cherry
Back To Basics, Index Performance, Index Scan, Index Seek, SQL Server, Table Scan

There are a few basic operations which SQL will perform when looking for the data that you need.  Here they are listed in the order of worst to best.

  • Table Scan
  • Clustered Index Scan
  • Index Scan
  • Clustered Index Seek
  • Index Seek
The...


1

Forgot Password

No problem! Submit your e-mail address below. We'll send you an e-mail containing your password.

Your password has been sent to: