Index: src/main/java/org/apache/hadoop/hbase/client/coprocessor/AggregationClient.java =================================================================== --- src/main/java/org/apache/hadoop/hbase/client/coprocessor/AggregationClient.java (revision 1306720) +++ src/main/java/org/apache/hadoop/hbase/client/coprocessor/AggregationClient.java (working copy) @@ -123,7 +123,8 @@ if (scan == null || (Bytes.equals(scan.getStartRow(), scan.getStopRow()) && !Bytes .equals(scan.getStartRow(), HConstants.EMPTY_START_ROW)) - || Bytes.compareTo(scan.getStartRow(), scan.getStopRow()) > 0) { + || ((Bytes.compareTo(scan.getStartRow(), scan.getStopRow()) > 0) && + !Bytes.equals(scan.getStopRow(), HConstants.EMPTY_END_ROW))) { throw new IOException( "Agg client Exception: Startrow should be smaller than Stoprow"); } else if (scan.getFamilyMap().size() != 1) {