From bcebad1d60898978c43715633b53a0e90a0bc57c Mon Sep 17 00:00:00 2001
From: Nikolai Kochetov <nik-kochetov@yandex-team.ru>
Date: Sat, 4 Apr 2020 18:37:31 +0300
Subject: [PATCH] Try fix aggregating.

---
 dbms/src/Processors/Merges/AggregatingSortedTransform.cpp | 4 ++--
 dbms/src/Processors/Merges/AggregatingSortedTransform.h   | 7 +++++++
 2 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/dbms/src/Processors/Merges/AggregatingSortedTransform.cpp b/dbms/src/Processors/Merges/AggregatingSortedTransform.cpp
index 82859559fb3..67b1289c4cc 100644
--- a/dbms/src/Processors/Merges/AggregatingSortedTransform.cpp
+++ b/dbms/src/Processors/Merges/AggregatingSortedTransform.cpp
@@ -185,7 +185,7 @@ void AggregatingSortedTransform::merge()
         if (key_differs)
         {
             /// Write the simple aggregation result for the previous group.
-            if (merged_data.mergedRows() > 0)
+            if (merged_data.isGroupStarted())
             {
                 insertSimpleAggregationResult();
                 merged_data.insertRow();
@@ -227,7 +227,7 @@ void AggregatingSortedTransform::merge()
     }
 
     /// Write the simple aggregation result for the previous group.
-    if (merged_data.mergedRows() > 0)
+    if (merged_data.isGroupStarted())
     {
         insertSimpleAggregationResult();
         merged_data.insertRow();
diff --git a/dbms/src/Processors/Merges/AggregatingSortedTransform.h b/dbms/src/Processors/Merges/AggregatingSortedTransform.h
index 7f32ed4eade..bb950a68257 100644
--- a/dbms/src/Processors/Merges/AggregatingSortedTransform.h
+++ b/dbms/src/Processors/Merges/AggregatingSortedTransform.h
@@ -63,10 +63,15 @@ private:
         {
             for (auto column_number : column_numbers)
                 columns[column_number]->insertFrom(*raw_columns[column_number], row);
+
+            is_group_started = true;
         }
 
+        bool isGroupStarted() const { return is_group_started; }
+
         void insertRow()
         {
+            is_group_started = false;
             ++total_merged_rows;
             ++merged_rows;
             /// TODO: sum_blocks_granularity += block_size;
@@ -81,6 +86,8 @@ private:
             for (auto & desc : def.columns_to_aggregate)
                 desc.column = typeid_cast<ColumnAggregateFunction *>(columns[desc.column_number].get());
         }
+    private:
+        bool is_group_started = false;
     };
 
     ColumnsDefinition columns_definition;