Category: SQL Server Internals

• A Join A Day – Predicate, Probe & Residual

  

  2012-12-24 - A Join A Day, General, Series, SQL Server Internals

  This article talks about predicates, probes and residuals, all of which are used in different places of different join queries. This knowledge can help you to identify why your join query is slow and where it is spending its time.

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• A Join A Day – The Hash Join

  

  2012-12-23 - A Join A Day, General, Performance, Series, SQL Server Internals

  This article introduces the Hash Join algorithm The Hash Join algorithm and shows in which situations it is a good choice. This algorithm is the most CPU and memory intensive one but if you are dealing with large tables it will often also be the fastest.

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• A Join A Day – The Sort Merge Join

  

  2012-12-22 - A Join A Day, General, Performance, Series, SQL Server Internals

  This article introduces the Sort Merge Join algorithm. It shows its strengths and weaknesses to help you identify query situations for which the Merge Join operator in the execution plan is an appropriate choice.

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• A Join A Day – The Nested Loops Join

  

  2012-12-21 - A Join A Day, General, Performance, Series, SQL Server Internals

  This article introduces the Nested Loops Join algorithm. It shows its strengths and weaknesses to help you identify query situations for which the Nested Loops Join operator in the execution plan is an appropriate choice.

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• Blob and Row Overflow Storage Internals – Row-Overflow Data

  

  2012-07-31 - General, SQL Server Internals

  Row-Overflow data storage is a mechanism that was introduce in SQL Server 2005. It allows for more flexibility when designing tables as it makes it possible to store more than 8060 byte in a single row. This article shows how this mechanism is working under the covers.

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