Filter Tree Optimization for Metric Qualifications

Filter tree optimization for metric qualifications is an advanced property that is hidden by default. For information on how to display this property, see Viewing and Changing Advanced VLDB Properties.

The Filter tree optimization for metric qualifications property determines whether metric qualifications that are included in separate passes of SQL are included in a single pass of SQL when possible. Metric qualifications can be included in separate passes of SQL in scenarios such as when the metric qualifications are used in filter definitions. Having a metric qualification at each logical level of a filter qualification can include each metric qualification in a separate pass of SQL. For example, consider a filter qualification that is structured as follows:

(AttributeQualfication1 AND MetricQualification1) AND (AttributeQualification2 AND MetricQualification2)

Since MetricQualification1 and MetricQualification2 are at separate logical levels of the filter qualification, this can cause each metric qualification to require its own pass of SQL.

You have the following options for this VLDB property:

• Enable Filter tree optimization for metric qualifications: Defines metric qualifications to be included in the same pass of SQL if possible. In the scenario described above, MetricQualification1 and MetricQualification2 are processed in the same pass of SQL. This can help to improve performance by reducing the number of SQL passes required.
• Disable Filter tree optimization for metric qualifications: Defines metric qualifications to be included in SQL passes based on their logical level in a filter qualification. In the scenario described above, MetricQualification1 and MetricQualification2 are processed in different passes of SQL.

Levels at Which You Can Set This

Report and project