Category: A Join A Day

• A Join A Day – New Year, New Join

  

  2012-12-31 - A Join A Day, Fundamentals, General, Series, T-SQL Statements

  While ANSI-92 joins have been around for over 20 years and the pre-ANSI-92 join syntax has been deprecated 4 SQL Server versions ago, it is still in use today. This article provides guidance on how to rewrite those old queries into the “new” outer form.

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• A Join A Day – The Merge Statement

  

  2012-12-30 - A Join A Day, Fundamentals, General, Series, T-SQL Statements

  SQL Server 2008 introduced a single statement insert-update-delete: MERGE. This article introduces this statement, explains how it works and shows that it is really a full outer join under the covers.

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• A Join A Day – UPDATE & DELETE

  

  2012-12-29 - A Join A Day, General, Series, T-SQL Statements

  Do you need to pull in data from several tables to update just one? This post shows how a join can be incorporated in an update or delete statement.

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• A Join A Day – Hash Join Limitations

  

  2012-12-28 - A Join A Day, General, Series, SQL Server Internals

  Which logical join types can be conquered by the Hash Join algorithm? Are there any special cases I need to be aware of for which the Hash Join operator might not be the best fit? Read on to get the answers.

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• A Join A Day – Merge Join Limitations

  

  2012-12-27 - A Join A Day, General, Series, SQL Server Internals

  The Merge Join algorithm is the fastest in many cases. But how do I know what is possible and more importantly when it is not a good choice at all to use the Merge Join operator in an execution plan?

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