Reading Query Plans

To better understand what the query processor is doing, we need a way to look at query plans. SQL Server 2005 has several different ways of displaying a query plan, and we refer to all these techniques collectively as “the showplan options.”

Query Plan Options

SQL Server 2005 supports three showplan options: graphical, text, and XML. Graphical and text were available in prior versions of SQL Server; XML is new to SQL Server 2005. Each showplan option outputs the same query plan. The difference between these options is how the information is formatted, the level of detail included, how we read it, and how we can use it.

Graphical Plans

The graphical showplan option uses visually appealing icons that correspond to the iterators ...

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