Bug 190739 [regression]Edit dataset from library cannot work properly[01]
data/org.eclipse.birt.report.data.adapter/src/org/eclipse/birt/report/data/adapter/impl/MetaDataPopulator.java
* COMPUTED_COLUMNS_PROP.
	 * 
	 * @throws BirtException
	 */
	public static IResultMetaData retrieveResultMetaData(
			DataSetHandle dataSetHandle ) throws BirtException
	{
		List resultSetList = null;
		if ( dataSetHandle instanceof OdaDataSetHandle )
		{
			resultSetList = (List) dataSetHandle.getProperty( OdaDataSetHandle.RESULT_SET_PROP );
		}
		else if( dataSetHandle instanceof ScriptDataSetHandle )
		{
			resultSetList = dataSetHandle.getListProperty( DataSetHandle.RESULT_SET_HINTS_PROP );
		}
		else
		{
			return null;
		}
		List computedList = (List) dataSetHandle.getProperty( OdaDataSetHandle.COMPUTED_COLUMNS_PROP );
		List columnMeta = new ArrayList( );
		ResultSetColumnDefinition columnDef;
		int count = 0;
		
		if ( resultSetList != null && resultSetList.size( ) > 0 )
		{
			ResultSetColumn resultSetColumn;
			HashSet orgColumnNameSet = new HashSet( );
			HashSet uniqueColumnNameSet = new HashSet( );