Improving query performance

This section focuses on access paths, a significant factor of DB2 performance. It explains what access paths are, how DB2 chooses them, what tools you can use to understand them, and how they affect performance.

Access paths: The key to query performance

An access path is the path that DB2 uses to locate data that is specified in SQL statements. An access path can be indexed or sequential.

Two big factors in the performance of an SQL statement are the amount of time that DB2 uses to determine the access path at run time and the efficiency of the access path. DB2 determines the access path for a statement either when you bind the plan or package that contains the SQL statement or when the SQL statement executes.

The ...

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