Fixed GridMergeIndexSorted compare routine. This closes
@@ -61,7 +61,9 @@ public final class GridMergeIndexSorted extends GridMergeIndex {
/** */
private final Comparator<RowStream> streamCmp = new Comparator<RowStream>() {
@Override public int compare(RowStream o1, RowStream o2) {
- // Nulls at the beginning.
+ if (o1 == o2) // both nulls
+ return 0;
+
if (o1 == null)
return -1;
