Optimizer Hints

You can specify three types of hints in a query to override the decisions made by the Query Optimizer:

• Table hints

• Join hints

• Query hints

The following sections examine and describe each type of table hint.

Forcing Index Selection with Table Hints

In addition to locking hints that can be specified for each table in a query, SQL Server 2008 allows you to provide table-level hints that enable you to specify the index SQL Server should use for accessing the table. The syntax for specifying an index hint is as follows:

SELECT column_list FROM tablename WITH (INDEX (indid | index_name [, ...]) )

This syntax allows you to specify multiple indexes. You can specify an index by name or by ID. It is recommended that you specify ...

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