KYLIN-3635 Percentile calculation on Spark engine is wrong
diff --git a/core-metadata/src/main/java/org/apache/kylin/measure/percentile/PercentileMeasureType.java b/core-metadata/src/main/java/org/apache/kylin/measure/percentile/PercentileMeasureType.java
index d95a054..0e0f1d2 100644
--- a/core-metadata/src/main/java/org/apache/kylin/measure/percentile/PercentileMeasureType.java
+++ b/core-metadata/src/main/java/org/apache/kylin/measure/percentile/PercentileMeasureType.java
@@ -82,6 +82,11 @@
                 }
                 return counter;
             }
+
+            @Override
+            public void reset() {
+                current = new PercentileCounter(dataType.getPrecision());
+            }
         };
     }