DRILL-4020: The not-equal operator returns incorrect results when used on the HBase row key

- Added a condition that checks if the filter to the scan specification doesn't have NOT_EQUAL operator
- Added testFilterPushDownRowKeyNotEqual() to TestHBaseFilterPushDown

closes #309

2 files changed, 19 insertions, 0 deletions

diff --git a/contrib/storage-hbase/src/main/java/org/apache/drill/exec/store/hbase/HBaseFilterBuilder.java b/contrib/storage-hbase/src/main/java/org/apache/drill/exec/store/hbase/HBaseFilterBuilder.java
index 8d2e8ffd7..6e1efe512 100644
--- a/contrib/storage-hbase/src/main/java/org/apache/drill/exec/store/hbase/HBaseFilterBuilder.java
+++ b/contrib/storage-hbase/src/main/java/org/apache/drill/exec/store/hbase/HBaseFilterBuilder.java
@@ -61,6 +61,7 @@ public class HBaseFilterBuilder extends AbstractExprVisitor<HBaseScanSpec, Void,
        * remove it since its effect is also achieved through startRow and stopRow.
        */
       if (parsedSpec.filter instanceof RowFilter &&
+          ((RowFilter)parsedSpec.filter).getOperator() != CompareOp.NOT_EQUAL &&
           ((RowFilter)parsedSpec.filter).getComparator() instanceof BinaryComparator) {
         parsedSpec.filter = null;
       }
diff --git a/contrib/storage-hbase/src/test/java/org/apache/drill/hbase/TestHBaseFilterPushDown.java b/contrib/storage-hbase/src/test/java/org/apache/drill/hbase/TestHBaseFilterPushDown.java
index e6eff116f..aee18eb70 100644
--- a/contrib/storage-hbase/src/test/java/org/apache/drill/hbase/TestHBaseFilterPushDown.java
+++ b/contrib/storage-hbase/src/test/java/org/apache/drill/hbase/TestHBaseFilterPushDown.java
@@ -45,6 +45,24 @@ public class TestHBaseFilterPushDown extends BaseHBaseTest {
   }
 
   @Test
+  public void testFilterPushDownRowKeyNotEqual() throws Exception {
+    setColumnWidths(new int[] {8, 38, 38});
+    final String sql = "SELECT\n"
+        + "  *\n"
+        + "FROM\n"
+        + "  hbase.`[TABLE_NAME]` tableName\n"
+        + "WHERE\n"
+        + "  row_key <> 'b4'";
+
+    runHBaseSQLVerifyCount(sql, 7);
+
+    final String[] expectedPlan = {".*startRow=, stopRow=, filter=RowFilter \\(NOT_EQUAL, b4\\).*"};
+    final String[] excludedPlan ={};
+    final String sqlHBase = canonizeHBaseSQL(sql);
+    PlanTestBase.testPlanMatchingPatterns(sqlHBase, expectedPlan, excludedPlan);
+  }
+
+  @Test
   public void testFilterPushDownRowKeyEqualWithItem() throws Exception {
     setColumnWidths(new int[] {20, 30});
     final String sql = "SELECT\n"