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
* @param queryDefn
	 * @param useColumnHints
	 * @param useFilters
	 * @return
	 * @throws BirtException
	 */
	public IQueryResults execute( DataSetHandle dataSet,
			QueryDefinition queryDefn, boolean useColumnHints,
			boolean useFilters, DataRequestSession session )
			throws BirtException
	{
		return this.execute( dataSet,
				queryDefn,
				useColumnHints,
				useFilters,
				false,
				session );
	}	
	
	/**
	 * 
	 * @param dataSet
	 * @param queryDefn
	 * @param useColumnHints
	 * @return
	 * @throws BirtException
	 */
	public IQueryResults execute( DataSetHandle dataSet,
			IQueryDefinition queryDefn, boolean useColumnHints,
			boolean useFilters, boolean clearCache,