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 orgColumnNameSet
	 * @param newColumnNameSet
	 * @param columnName
	 * @param index
	 * @return
	 */
	private String getUniqueName( HashSet orgColumnNameSet,
			HashSet newColumnNameSet, String columnName, int index )
	{
		String newColumnName;
		if ( columnName == null
				|| columnName.trim( ).length( ) == 0
				|| newColumnNameSet.contains( columnName ) )
		{
			
			if ( columnName == null || columnName.trim( ).length( ) == 0 )
				newColumnName = UNNAME_PREFIX
						+ RENAME_SEPARATOR + String.valueOf( index + 1 );
			else
				newColumnName = columnName
						+ RENAME_SEPARATOR + String.valueOf( index + 1 );
			int i = 1;
			while ( orgColumnNameSet.contains( newColumnName )
					|| newColumnNameSet.contains( newColumnName ) )
			{
				newColumnName += String.valueOf( RENAME_SEPARATOR ) + i;
				i++;
			}