From f683437a8cb0cd40f0cc45ab4745824028e3949a Mon Sep 17 00:00:00 2001
From: chertus <chertus@gmail.com>
Date: Thu, 20 Feb 2020 20:19:16 +0300
Subject: [PATCH] remove dangerous optimisation

---
 dbms/src/Interpreters/JoinSwitcher.cpp | 5 -----
 dbms/src/Interpreters/JoinSwitcher.h   | 2 +-
 2 files changed, 1 insertion(+), 6 deletions(-)

diff --git a/dbms/src/Interpreters/JoinSwitcher.cpp b/dbms/src/Interpreters/JoinSwitcher.cpp
index d500f55fc5a..142a7a1af94 100644
--- a/dbms/src/Interpreters/JoinSwitcher.cpp
+++ b/dbms/src/Interpreters/JoinSwitcher.cpp
@@ -31,11 +31,6 @@ JoinSwitcher::JoinSwitcher(std::shared_ptr<AnalyzedJoin> table_join_, const Bloc
 
 bool JoinSwitcher::addJoinedBlock(const Block & block, bool)
 {
-    /// Trying to make MergeJoin without lock
-
-    if (switched.load(std::memory_order_relaxed))
-        return join->addJoinedBlock(block);
-
     std::lock_guard lock(switch_mutex);
 
     if (switched)
diff --git a/dbms/src/Interpreters/JoinSwitcher.h b/dbms/src/Interpreters/JoinSwitcher.h
index 487f35d4d6b..47ed2b8bc57 100644
--- a/dbms/src/Interpreters/JoinSwitcher.h
+++ b/dbms/src/Interpreters/JoinSwitcher.h
@@ -64,7 +64,7 @@ public:
 private:
     JoinPtr join;
     SizeLimits limits;
-    mutable std::atomic<bool> switched;
+    bool switched;
     mutable std::mutex switch_mutex;
     std::shared_ptr<AnalyzedJoin> table_join;
     const Block right_sample_block;