Search space and heuristics

The Query Optimizer uses a framework to search and compare many different possible plan alternatives efficiently. This framework allows SQL Server to consider complex, nonobvious ways to implement a certain query. Keeping track of all these different alternatives to find a plan to run efficiently isn’t easy. The search framework of SQL Server contains several components that help it perform its job efficiently and reliably. Although largely internal, these components are described in this section to give you a better idea about how a query is optimized and how to better design your applications to take advantage of its capabilities.


The Query Optimizer is a search framework. The Query Optimizer considers transformations ...

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