Bug 213126 Add support for DataEngine-leve dataset cache
In many cases the DataEngine-leve dataset cache is useful which ensure that a dataset is executed one time during rendering one report. To support this feature a new dataset property should be added. The Birt customer can choose whether this dataset need to be cached or not by setting the property in deisgn time.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/api/DataSetHandle.java
import org.eclipse.birt.report.model.api.elements.structures.DataSetParameter;
import org.eclipse.birt.report.model.api.elements.structures.FilterCondition;
import org.eclipse.birt.report.model.api.metadata.PropertyValueException;
import org.eclipse.birt.report.model.core.DesignElement;
import org.eclipse.birt.report.model.core.Module;
import org.eclipse.birt.report.model.elements.interfaces.IDataSetModel;
import org.eclipse.birt.report.model.elements.interfaces.IImageItemModel;
import org.eclipse.birt.report.model.elements.interfaces.IReportItemModel;
import org.eclipse.birt.report.model.elements.interfaces.ISimpleDataSetModel;
import org.eclipse.birt.report.model.metadata.ElementPropertyDefn;
/**
 * Abstract handle for data set elements. A data set is a named object that
 * provides a result set defined as a sequence of data rows. Report elements use
 * data sets to retrieve data for display.
 * <p>
 * A data set has three key parts:
 * <p>
 * <ul>
 * <li>Data access: Retrieving data from an external data source.
 * <li>Report-specific properties: Properties for how the data is to be used in
 * the report such as rules for searching, data export and so on.
 * <li>Data transforms: Rules for processing the data for use by the report.
 * Data transforms are most frequently defined by report items that use the data
 * set, and are applied to the result set by BIRT.
 * </ul>
 * <p>
 * Data transforms that can be defined on a data set include:
 * <ul>
 * <li>Column projections: identifying additional required columns, assigning
 * column aliases, and providing column meta-data.