Bug 147101 Report generation performance is sluggish
The overall performance of report generation appears to be quite sluggish. Here are numbers that we have measured using ORACLE as a DB. We use ORACLE 10g w/ojdbc14.jar thin driver. select rownum, datetime_id, another_id, text from ( select max(datetime_id) as datetime_id, another_id, text from some_oracle_schema.sample_table where text < 'c%' group by another_id, text ) Query resulting in 8465 rows Using PL/SQL developer: ----------------------- Execution: approx 1 second Iterating through all rows via PL/SQL developer UI: 10 seconds BIRT: ----- Preview page (via dataset editor): shows all 8465 rows in 53 seconds Preview tab (in the designer): shows all 8465 rows in 79 seconds Generation of rptdocument from rptdesign using API: 55 seconds
data/org.eclipse.birt.data/src/org/eclipse/birt/data/engine/executor/transform/group/GroupCalculationUtil.java
*/
final class GroupBoundaryInfo implements ICachedObject
{
	
	private int startIndex;
	private int endIndex;
	
	private Object[] sortKeys;
	private boolean[] sortDirections;
	
	private boolean accept = true;
	/**
	 * 
	 * @return
	 */
	public static ICachedObjectCreator getCreator()
	{
		return new GroupBoundaryInfoCreator();
	}
	
	/**
	 * @param start
	 *            The start index of a group
	 * @param end
	 *            The end index of a group
	 */
	GroupBoundaryInfo( int start, int end )
	{
		this.startIndex = start;
		this.endIndex = end;