How the Query Optimizer Explores Query Plans

The Query Optimizer uses a framework to search and compare many different possible plan alternatives efficiently. This framework allows SQL Server to consider complex, non-obvious ways to implement a given query. Keeping track of all these different alternatives to find a plan to run efficiently is not 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 to better design your applications to take advantage of its capabilities.

Rules

The Query Optimizer is a search framework. From a given query tree, ...

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