From 5d394a20a162d0af7115a5d03708e91843b6c6cf Mon Sep 17 00:00:00 2001
From: Alexey Milovidov <milovidov@yandex-team.ru>
Date: Tue, 1 Nov 2016 18:22:04 +0300
Subject: [PATCH] MergeSelector: changed logic of selection of parts for
 OPTIMIZE (more like it was before) [#METR-21841].

---
 dbms/src/Storages/MergeTree/MergeTreeDataMerger.cpp | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/dbms/src/Storages/MergeTree/MergeTreeDataMerger.cpp b/dbms/src/Storages/MergeTree/MergeTreeDataMerger.cpp
index ffa09c4405..a272e5e690 100644
--- a/dbms/src/Storages/MergeTree/MergeTreeDataMerger.cpp
+++ b/dbms/src/Storages/MergeTree/MergeTreeDataMerger.cpp
@@ -139,13 +139,12 @@ bool MergeTreeDataMerger::selectPartsToMerge(
 
 	std::unique_ptr<IMergeSelector> merge_selector;
 
+	SimpleMergeSelector::Settings merge_settings;
 	if (aggressive)
-		merge_selector = std::make_unique<AllMergeSelector>();
-	else
-	{
-		SimpleMergeSelector::Settings merge_settings;
-		merge_selector = std::make_unique<SimpleMergeSelector>(merge_settings);
-	}
+		merge_settings.base = 1;
+
+	/// NOTE Could allow selection of different merge strategy.
+	merge_selector = std::make_unique<SimpleMergeSelector>(merge_settings);
 
 	IMergeSelector::PartsInPartition parts_to_merge = merge_selector->select(
 		partitions,
-- 
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