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pingcap · Jul 1, 2022 · fd870e7 · fd870e7
1 parent fceb508
commit fd870e7
Showing 1 changed file with 4 additions and 0 deletions.
diff --git a/tikv-client/src/main/java/com/pingcap/tikv/operation/iterator/ConcreteScanIterator.java b/tikv-client/src/main/java/com/pingcap/tikv/operation/iterator/ConcreteScanIterator.java
@@ -65,6 +65,10 @@ TiRegion loadCurrentRegionToCache() throws GrpcException {
           try {
             int scanSize = Math.min(limit, conf.getScanBatchSize());
             currentCache = client.scan(backOffer, startKey, scanSize, version);
+            // If we get region before scan, we will use region from cache which
+            // may have wrong end key. This may miss some regions that split from old region.
+            // Client will get the newest region during scan. So we need to
+            // update region after scan.
             region = client.getRegion();
           } catch (final TiKVException e) {
             backOffer.doBackOff(BackOffFunction.BackOffFuncType.BoRegionMiss, e);