Category: General

• A Join A Day – The Right Semi Join

  

  2012-12-13 - A Join A Day, Fundamentals, General, Series

  The right semi join works like the left semi join, it just switches the role of the two sides. A Right Semi Join returns only rows from the right side base on the existence of matching rows on the left.

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• A Join A Day – The Left Semi Join

  

  2012-12-12 - A Join A Day, Fundamentals, General, Series

  The Left Semi Join is a half join: It only includes rows from the left side in the results. A typical example for a left semi join query is a statement containing the EXEISTS keyword. However, this does not always result in an execution plan with a Left Semi Join operator.

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• A Join A Day – How to Test a Join

  

  2012-12-11 - A Join A Day, General, Series, T-SQL Tuesday, TDD, tSQLt

  This is an advanced article showing how to use the “0-1-some” heuristic to select the right test cases when unit testing a join query. The example will approach the task following Test Driven Design.

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• A Join A Day – A Self-Join Experience

  

  2012-12-10 - A Join A Day, Fundamentals, General, Series

  A self-join is not something that is provided by a special join command. It’s just a term for the pretty mundane idea of joining a table to itself. But rest assured – there is more behind it… [more…]

• A Join A Day – The Outer Apply

  

  2012-12-09 - A Join A Day, Fundamentals, General, Series, T-SQL Statements

  This is day nine of the A Join A Day series and we are going to look at the outer apply statement. We will discover the differences to the cross apply and the similarities to the left outer join. Read on to get all the details.

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