Abstract: Techniques are provided for a fully-automated process for tuning database query language statements that selects database query language statements for tuning, tunes the database query language statements and generates tuning recommendations, tests the tuning recommendations, and determines whether to implement the tuning recommendations based on the test results. The fully-automated tuning process may also automatically implement certain tuning recommendations and monitor the performance of the database query language statements for which tuning recommendations have been implemented.

Abstract: A run-away query execution is automatically identified by a background process that periodically looks at each of the currently executing queries and compares the current execution time with the execution time estimated by the optimizer. Each query execution having a negative execution time difference can be automatically identified as a run-away query execution. The query execution plans that result in run-away executions can then be automatically tuned to produce more efficient execution plans.

Abstract: A persistent data structure for storing a profile of tuning information for a query statement separately from the query statement is disclosed. The persistent data structure includes a statement signature to identify the statement, and an action to tune the statement.

Abstract: A method of storing one or more database query language statements and performance information for each statement as a persistent database object is disclosed.

Abstract: A method for receiving a database query language statement and performance information about the statement at an optimizer and generating one or more tuning actions for the statement with the performance information is disclosed.

Abstract: A method of gathering performance information about a workload, and automatically identifying a set of high-load database query language statements from the workload based on the performance information, is disclosed.

Abstract: A method to addresses structural performance problems of a database query language statement is provided. The method includes receiving a database query language statement at an optimizer, evaluating choices in a search space to generate an execution plan for the statement, and producing annotations to record one or more reasons for selecting each choice while generating the execution plan.