Bug 168026 Still use the existing data binding even though the aggregate is different
I had a table in which a data binding which aggregates on a group. When I insert a new data item in the report, although the expressions are same, it aggregates on All, then it refered to the existing data binding. The expected behavior would be a new data binding is created with different aggregates.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/api/ReportItemHandle.java
public TOCHandle addTOC( TOC toc ) throws SemanticException
	{
		setProperty( IReportItemModel.TOC_PROP, toc );
		if ( toc == null )
			return null;
		return (TOCHandle) toc
				.getHandle( getPropertyHandle( IReportItemModel.TOC_PROP ) );
	}
	/**
	 * Gets the item's z position as an integer.
	 * 
	 * @return the z depth. Start from 0
	 */
	public int getZIndex( )
	{
		return super.getIntProperty( IReportItemModel.Z_INDEX_PROP );
	}
	/**
	 * Sets the item's z position to an integer.
	 * 
	 * @param zIndex
	 *            the z depth. Start from 0
	 * @throws SemanticException
	 *             if the property is locked.
	 */
	public void setZIndex( int zIndex ) throws SemanticException
	{
		setIntProperty( IReportItemModel.Z_INDEX_PROP, zIndex );
	}
}