Bug 131011 Support running query based on report document data
Data Engine should support running a query based on data set and expression data stored in a report document. This bugzilla entry serves as a repository for design docs and notes related to this feature.
data/org.eclipse.birt.data/src/org/eclipse/birt/data/engine/impl/QueryExecutor.java
*/
	public IResultMetaData getResultMetaData( ) throws DataException
	{
		assert odiQuery instanceof IPreparedDSQuery
				|| odiQuery instanceof ICandidateQuery
				|| odiQuery instanceof JointDataSetQuery;
				
		if ( odiQuery instanceof IPreparedDSQuery )
		{
			if ( ( (IPreparedDSQuery) odiQuery ).getResultClass( ) != null )
				return new ResultMetaData( ( (IPreparedDSQuery) odiQuery ).getResultClass( ) );
			else
			    return null;
		}
		else if ( odiQuery instanceof JointDataSetQuery )
		{
			return new ResultMetaData( ( (JointDataSetQuery) odiQuery ).getResultClass( ) );
		}
		else
		{
			return new ResultMetaData( ( (ICandidateQuery) odiQuery ).getResultClass( ) );
		}
	}
	
	/*
	 * @see org.eclipse.birt.data.engine.impl.IQueryExecutor#execute()
	 */
	public void execute( IEventHandler eventHandler ) throws DataException
	{
		logger.logp( Level.FINER,