From acae5c1c9bf943126a621e6e7e3e22d01aa0455e Mon Sep 17 00:00:00 2001
From: SeaRise <hhssearise@foxmail.com>
Date: Mon, 7 Mar 2022 18:21:49 +0800
Subject: [PATCH] fix bug  from pull request 4042 (#4190)

ref pingcap/tics#4118
---
 dbms/src/Flash/Coprocessor/DAGExpressionAnalyzer.cpp | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/dbms/src/Flash/Coprocessor/DAGExpressionAnalyzer.cpp b/dbms/src/Flash/Coprocessor/DAGExpressionAnalyzer.cpp
index 0ec728c3f18..1ef990f0889 100644
--- a/dbms/src/Flash/Coprocessor/DAGExpressionAnalyzer.cpp
+++ b/dbms/src/Flash/Coprocessor/DAGExpressionAnalyzer.cpp
@@ -386,12 +386,11 @@ std::tuple<Names, TiDB::TiDBCollators, AggregateDescriptions, ExpressionActionsP
     chain.finalize();
     chain.clear();
 
-    initChain(chain, getCurrentInputColumns());
-    const auto & actions = chain.getLastActions();
-    appendCastAfterAgg(actions, agg);
+    auto & after_agg_step = initAndGetLastStep(chain);
+    appendCastAfterAgg(after_agg_step.actions, agg);
     // after appendCastAfterAgg, current input columns has been modified.
     for (const auto & column : getCurrentInputColumns())
-        step.required_output.push_back(column.name);
+        after_agg_step.required_output.push_back(column.name);
 
     return {aggregation_keys, collators, aggregate_descriptions, before_agg};
 }