Bug 207564 Column sorting based on data type
Only string sorting happens when a column is selected in preview result page of DataSet Editor irrespective of type of data shown in that column. I'd like to be able to sort the data based on its datatype when a column is selected.
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/data/ui/util/DataSetProvider.java
DataRequestSession session ) throws BirtException
	{
		IBaseDataSetDesign dataSetDesign = session.getModelAdaptor( )
				.adaptDataSet( dataSet );
		if ( clearCache )
		{
			IBaseDataSourceDesign dataSourceDesign = session.getModelAdaptor( )
					.adaptDataSource( dataSet.getDataSource( ) );
			session.clearCache( dataSourceDesign, dataSetDesign );
		}
		if ( !useColumnHints )
		{
			dataSetDesign.getResultSetHints( ).clear( );
		}
		if ( !useFilters )
		{
			dataSetDesign.getFilters( ).clear( );
		}
		IQueryResults resultSet = executeQuery( session, queryDefn );
		saveResultToDataItems( dataSet, resultSet );
		return resultSet;
	}
	
	/**
	 * 
	 * @param dataSet
	 * @param resultSet
	 * @throws BirtException
	 */
	private void saveResultToDataItems( DataSetHandle dataSet,