Bug 151535 Parameters are invisable in Joint Dataset
Trying to use "Joint Dataset" combined with parameters within underlaying Data-Sets (neccessary to achive a filtering where clause for a DateTime Field) Parameter editing ( e.g. in Chart designer) do not show the entire parameter. As specified it should show and let to edit a combination of both underlaying datasets' parameters.
data/org.eclipse.birt.data/src/org/eclipse/birt/data/engine/impl/PreparedJointDataSourceQuery.java
*/
	private JointResultMetadata getJointResultMetadata( IResultMetaData left,
			IResultMetaData right ) throws DataException
	{
		
		if ( left == null || right == null )
		{
			throw new DataException( ResourceConstants.UNEXPECTED_ERROR );
		}
		try
		{
			String leftPrefix = dataSet.getLeftDataSetDesignName( );
			String rightPrefix = dataSet.getRightDataSetDesignName( );
			if ( leftPrefix.equals( rightPrefix ) )
			{
				leftPrefix = leftPrefix + "1";
				rightPrefix = rightPrefix + "2";
			}
			leftPrefix = leftPrefix + COLUMN_NAME_SPLITTER;
			rightPrefix = rightPrefix + COLUMN_NAME_SPLITTER;
			JointResultMetadata meta = populatorJointResultMetadata( left,
					leftPrefix,
					right,
					rightPrefix );
			return meta;
		}
		catch ( BirtException be )
		{
			throw DataException.wrap( be );
		}