for(DefinitionSource eachSource : definition.getSources()){
														scanRDD2.union(context.parallelize(Collections.singletonList(new Tuple2<>(
																lookupService.scan(context,transUtils.tableName(eachSource.getSchemaName(),
																eachSource.getTableName()),param.getTimeSlot(),eachSource.getTimelineKey()).collect(),
																new SourceParam(eachSource,param)))));
												}