HBASE-17318 Increment does not add new column if the increment amount is zero at first time writing (Guangxu Cheng)

hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/HRegion.java

@@ -7508,12 +7508,15 @@ public class HRegion implements HeapSize, PropagatingConfigurationObserver, Regi
     for (int i = 0; i < deltas.size(); i++) {
       Cell delta = deltas.get(i);
       Cell currentValue = null;
+      boolean firstWrite = false;
       if (currentValuesIndex < currentValues.size() &&
           CellUtil.matchingQualifier(currentValues.get(currentValuesIndex), delta)) {
         currentValue = currentValues.get(currentValuesIndex);
         if (i < (deltas.size() - 1) && !CellUtil.matchingQualifier(delta, deltas.get(i + 1))) {
           currentValuesIndex++;
         }
+      } else {
+        firstWrite = true;
       }
       // Switch on whether this an increment or an append building the new Cell to apply.
       Cell newCell = null;
@@ -7542,7 +7545,7 @@ public class HRegion implements HeapSize, PropagatingConfigurationObserver, Regi
             coprocessorHost.postMutationBeforeWAL(mutationType, mutation, currentValue, newCell);
       }
       // If apply, we need to update memstore/WAL with new value; add it toApply.
-      if (apply) {
+      if (apply || firstWrite) {
         toApply.add(newCell);
       }
       // Add to results to get returned to the Client. If null, cilent does not want results.

hbase-server/src/test/java/org/apache/hadoop/hbase/client/TestIncrementsFromClientSide.java

@@ -19,6 +19,7 @@
 package org.apache.hadoop.hbase.client;
 
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
 import static org.junit.Assert.assertTrue;
 import static org.junit.Assert.fail;
 
@@ -345,6 +346,49 @@ public class TestIncrementsFromClientSide {
     ht.close();
   }
 
+  @Test
+  public void testIncrementIncrZeroAtFirst() throws Exception {
+    LOG.info("Starting " + this.name.getMethodName());
+    final TableName TABLENAME =
+            TableName.valueOf(filterStringSoTableNameSafe(this.name.getMethodName()));
+    Table ht = TEST_UTIL.createTable(TABLENAME, FAMILY);
+
+    byte[] col1 = Bytes.toBytes("col1");
+    byte[] col2 = Bytes.toBytes("col2");
+    byte[] col3 = Bytes.toBytes("col3");
+
+    // Now increment zero at first time incr
+    Increment inc = new Increment(ROW);
+    inc.addColumn(FAMILY, col1, 0);
+    ht.increment(inc);
+
+    // Verify expected results
+    Get get = new Get(ROW);
+    Result r = ht.get(get);
+    Cell [] kvs = r.rawCells();
+    assertEquals(1, kvs.length);
+    assertNotNull(kvs[0]);
+    assertIncrementKey(kvs[0], ROW, FAMILY, col1, 0);
+
+    // Now try multiple columns by different amounts
+    inc = new Increment(ROW);
+    inc.addColumn(FAMILY, col1, 1);
+    inc.addColumn(FAMILY, col2, 0);
+    inc.addColumn(FAMILY, col3, 2);
+    ht.increment(inc);
+    // Verify
+    get = new Get(ROW);
+    r = ht.get(get);
+    kvs = r.rawCells();
+    assertEquals(3, kvs.length);
+    assertNotNull(kvs[0]);
+    assertNotNull(kvs[1]);
+    assertNotNull(kvs[2]);
+    assertIncrementKey(kvs[0], ROW, FAMILY, col1, 1);
+    assertIncrementKey(kvs[1], ROW, FAMILY, col2, 0);
+    assertIncrementKey(kvs[2], ROW, FAMILY, col3, 2);
+  }
+
   @Test
   public void testIncrement() throws Exception {
     LOG.info("Starting " + this.name.getMethodName());

hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/wal/TestDurability.java

@@ -177,24 +177,32 @@ public class TestDurability {
     final WAL wal = wals.getWAL(tableName, null);
     HRegion region = createHRegion(tableName, "increment", wal, Durability.USE_DEFAULT);
 
-    // col1: amount = 1, 1 write back to WAL
+    // col1: amount = 0, 1 write back to WAL
     Increment inc1 = new Increment(row1);
-    inc1.addColumn(FAMILY, col1, 1);
+    inc1.addColumn(FAMILY, col1, 0);
     Result res = region.increment(inc1);
     assertEquals(1, res.size());
-    assertEquals(1, Bytes.toLong(res.getValue(FAMILY, col1)));
+    assertEquals(0, Bytes.toLong(res.getValue(FAMILY, col1)));
     verifyWALCount(wals, wal, 1);
 
+    // col1: amount = 1, 1 write back to WAL
+    inc1 = new Increment(row1);
+    inc1.addColumn(FAMILY, col1, 1);
+    res = region.increment(inc1);
+    assertEquals(1, res.size());
+    assertEquals(1, Bytes.toLong(res.getValue(FAMILY, col1)));
+    verifyWALCount(wals, wal, 2);
+
     // col1: amount = 0, 0 write back to WAL
     inc1 = new Increment(row1);
     inc1.addColumn(FAMILY, col1, 0);
     res = region.increment(inc1);
     assertEquals(1, res.size());
     assertEquals(1, Bytes.toLong(res.getValue(FAMILY, col1)));
-    verifyWALCount(wals, wal, 1);
+    verifyWALCount(wals, wal, 2);
 
     // col1: amount = 0, col2: amount = 0, col3: amount = 0
-    // 0 write back to WAL
+    // 1 write back to WAL
     inc1 = new Increment(row1);
     inc1.addColumn(FAMILY, col1, 0);
     inc1.addColumn(FAMILY, col2, 0);
@@ -204,7 +212,7 @@ public class TestDurability {
     assertEquals(1, Bytes.toLong(res.getValue(FAMILY, col1)));
     assertEquals(0, Bytes.toLong(res.getValue(FAMILY, col2)));
     assertEquals(0, Bytes.toLong(res.getValue(FAMILY, col3)));
-    verifyWALCount(wals, wal, 1);
+    verifyWALCount(wals, wal, 3);
 
     // col1: amount = 5, col2: amount = 4, col3: amount = 3
     // 1 write back to WAL
@@ -217,7 +225,7 @@ public class TestDurability {
     assertEquals(6, Bytes.toLong(res.getValue(FAMILY, col1)));
     assertEquals(4, Bytes.toLong(res.getValue(FAMILY, col2)));
     assertEquals(3, Bytes.toLong(res.getValue(FAMILY, col3)));
-    verifyWALCount(wals, wal, 2);
+    verifyWALCount(wals, wal, 4);
   }
   
   /*