diff --git a/src/Interpreters/MergeJoin.cpp b/src/Interpreters/MergeJoin.cpp
index a9f50cdda0e..26463c8c6ed 100644
--- a/src/Interpreters/MergeJoin.cpp
+++ b/src/Interpreters/MergeJoin.cpp
@@ -464,6 +464,12 @@ MergeJoin::MergeJoin(std::shared_ptr<TableJoin> table_join_, const Block & right
                             ErrorCodes::PARAMETER_OUT_OF_BOUND);
     }
 
+    for (const auto & right_key : table_join->keyNamesRight())
+    {
+        if (right_sample_block.getByName(right_key).type->lowCardinality())
+            lowcard_right_keys.push_back(right_key);
+    }
+
     table_join->splitAdditionalColumns(right_sample_block, right_table_keys, right_columns_to_add);
     JoinCommon::removeLowCardinalityInplace(right_table_keys);
     JoinCommon::removeLowCardinalityInplace(right_sample_block, table_join->keyNamesRight());
@@ -607,10 +613,18 @@ bool MergeJoin::addJoinedBlock(const Block & src_block, bool)
 
 void MergeJoin::joinBlock(Block & block, ExtraBlockPtr & not_processed)
 {
+    Names lowcard_keys = lowcard_right_keys;
     if (block)
     {
         JoinCommon::checkTypesOfKeys(block, table_join->keyNamesLeft(), right_table_keys, table_join->keyNamesRight());
         materializeBlockInplace(block);
+
+        for (const auto & column_name : table_join->keyNamesLeft())
+        {
+            if (block.getByName(column_name).type->lowCardinality())
+                lowcard_keys.push_back(column_name);
+        }
+
         JoinCommon::removeLowCardinalityInplace(block, table_join->keyNamesLeft(), false);
 
         sortBlock(block, left_sort_description);
@@ -646,14 +660,20 @@ void MergeJoin::joinBlock(Block & block, ExtraBlockPtr & not_processed)
     if (!not_processed && left_blocks_buffer)
         not_processed = std::make_shared<NotProcessed>(NotProcessed{{}, 0, 0, 0});
 
+    for (const auto & column_name : lowcard_keys)
+    {
+        if (!block.has(column_name))
+            continue;
+        if (auto & col = block.getByName(column_name); !col.type->lowCardinality())
+            JoinCommon::changeLowCardinalityInplace(col);
+    }
+
     JoinCommon::restoreLowCardinalityInplace(block);
 }
 
 template <bool in_memory, bool is_all>
 void MergeJoin::joinSortedBlock(Block & block, ExtraBlockPtr & not_processed)
 {
-    //std::shared_lock lock(rwlock);
-
     size_t rows_to_reserve = is_left ? block.rows() : 0;
     MutableColumns left_columns = makeMutableColumns(block, (is_all ? rows_to_reserve : 0));
     MutableColumns right_columns = makeMutableColumns(right_columns_to_add, rows_to_reserve);
@@ -702,7 +722,6 @@ void MergeJoin::joinSortedBlock(Block & block, ExtraBlockPtr & not_processed)
 
         left_cursor.nextN(left_key_tail);
         joinInequalsLeft<is_all>(block, left_columns, right_columns_to_add, right_columns, left_cursor.position(), left_cursor.end());
-        //left_cursor.nextN(left_cursor.end() - left_cursor.position());
 
         changeLeftColumns(block, std::move(left_columns));
         addRightColumns(block, std::move(right_columns));
diff --git a/src/Interpreters/MergeJoin.h b/src/Interpreters/MergeJoin.h
index f286e74b385..b6bde8fb131 100644
--- a/src/Interpreters/MergeJoin.h
+++ b/src/Interpreters/MergeJoin.h
@@ -103,6 +103,8 @@ private:
     const size_t max_rows_in_right_block;
     const size_t max_files_to_merge;
 
+    Names lowcard_right_keys;
+
     void changeLeftColumns(Block & block, MutableColumns && columns) const;
     void addRightColumns(Block & block, MutableColumns && columns);
 
diff --git a/tests/queries/0_stateless/01049_join_low_card_bug.reference b/tests/queries/0_stateless/01049_join_low_card_bug.reference
index d3610bb97cf..c6de3c202d7 100644
--- a/tests/queries/0_stateless/01049_join_low_card_bug.reference
+++ b/tests/queries/0_stateless/01049_join_low_card_bug.reference
@@ -199,3 +199,204 @@ LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	\N	\N	Nullable
 LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	str	str	Nullable(String)	Nullable(String)	str	str
 LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	\N	\N	Nullable(String)	Nullable(String)	str_l	str_l
 LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	str_r	str_r	Nullable(String)	Nullable(String)	\N	\N
+str	LowCardinality(String)
+	LowCardinality(String)
+str_r	LowCardinality(String)
+str	LowCardinality(String)
+str	LowCardinality(String)
+	LowCardinality(String)
+str_l	LowCardinality(String)
+str_r	LowCardinality(String)
+str	LowCardinality(String)
+str_l	LowCardinality(String)
+LowCardinality(String)	LowCardinality(String)	str	str	LowCardinality(String)	LowCardinality(String)	str	str
+LowCardinality(String)	LowCardinality(String)	str_r	str_r	LowCardinality(String)	LowCardinality(String)		
+LowCardinality(String)	LowCardinality(String)	str_r	str_r	LowCardinality(String)	LowCardinality(String)		
+LowCardinality(String)	LowCardinality(String)	str	str	LowCardinality(String)	LowCardinality(String)	str	str
+LowCardinality(String)	LowCardinality(String)	str	str	LowCardinality(String)	LowCardinality(String)	str	str
+LowCardinality(String)	LowCardinality(String)	str_r	str_r	LowCardinality(String)	LowCardinality(String)		
+LowCardinality(String)	LowCardinality(String)			LowCardinality(String)	LowCardinality(String)	str_l	str_l
+LowCardinality(String)	LowCardinality(String)	str_r	str_r	LowCardinality(String)	LowCardinality(String)		
+LowCardinality(String)	LowCardinality(String)	str	str	LowCardinality(String)	LowCardinality(String)	str	str
+LowCardinality(String)	LowCardinality(String)			LowCardinality(String)	LowCardinality(String)	str_l	str_l
+str	LowCardinality(String)
+	LowCardinality(String)
+str_r	LowCardinality(String)
+str	LowCardinality(String)
+str	LowCardinality(String)
+	LowCardinality(String)
+str_l	LowCardinality(String)
+str_r	LowCardinality(String)
+str	LowCardinality(String)
+str_l	LowCardinality(String)
+String	String	str	str	LowCardinality(String)	LowCardinality(String)	str	str
+String	String	str_r	str_r	LowCardinality(String)	LowCardinality(String)		
+String	String	str_r	str_r	LowCardinality(String)	LowCardinality(String)		
+String	String	str	str	LowCardinality(String)	LowCardinality(String)	str	str
+String	String	str	str	LowCardinality(String)	LowCardinality(String)	str	str
+String	String	str_r	str_r	LowCardinality(String)	LowCardinality(String)		
+String	String			LowCardinality(String)	LowCardinality(String)	str_l	str_l
+String	String	str_r	str_r	LowCardinality(String)	LowCardinality(String)		
+String	String	str	str	LowCardinality(String)	LowCardinality(String)	str	str
+String	String			LowCardinality(String)	LowCardinality(String)	str_l	str_l
+str	String
+	String
+str_r	String
+str	String
+str	String
+	String
+str_l	String
+str_r	String
+str	String
+str_l	String
+LowCardinality(String)	LowCardinality(String)	str	str	String	String	str	str
+LowCardinality(String)	LowCardinality(String)	str_r	str_r	String	String		
+LowCardinality(String)	LowCardinality(String)	str_r	str_r	String	String		
+LowCardinality(String)	LowCardinality(String)	str	str	String	String	str	str
+LowCardinality(String)	LowCardinality(String)	str	str	String	String	str	str
+LowCardinality(String)	LowCardinality(String)	str_r	str_r	String	String		
+LowCardinality(String)	LowCardinality(String)			String	String	str_l	str_l
+LowCardinality(String)	LowCardinality(String)	str_r	str_r	String	String		
+LowCardinality(String)	LowCardinality(String)	str	str	String	String	str	str
+LowCardinality(String)	LowCardinality(String)			String	String	str_l	str_l
+str	LowCardinality(String)
+	LowCardinality(String)
+str_r	LowCardinality(String)
+str	LowCardinality(String)
+str	LowCardinality(String)
+	LowCardinality(String)
+str_l	LowCardinality(String)
+str_r	LowCardinality(String)
+str	LowCardinality(String)
+str_l	LowCardinality(String)
+Nullable(String)	Nullable(String)	str	str	LowCardinality(String)	LowCardinality(String)	str	str
+Nullable(String)	Nullable(String)	str_r	str_r	LowCardinality(String)	LowCardinality(String)		
+Nullable(String)	Nullable(String)	str_r	str_r	LowCardinality(String)	LowCardinality(String)		
+Nullable(String)	Nullable(String)	str	str	LowCardinality(String)	LowCardinality(String)	str	str
+Nullable(String)	Nullable(String)	str	str	LowCardinality(String)	LowCardinality(String)	str	str
+Nullable(String)	Nullable(String)	str_r	str_r	LowCardinality(String)	LowCardinality(String)		
+Nullable(String)	Nullable(String)	\N	\N	LowCardinality(String)	LowCardinality(String)	str_l	str_l
+Nullable(String)	Nullable(String)	str_r	str_r	LowCardinality(String)	LowCardinality(String)		
+Nullable(String)	Nullable(String)	str	str	LowCardinality(String)	LowCardinality(String)	str	str
+Nullable(String)	Nullable(String)	\N	\N	LowCardinality(String)	LowCardinality(String)	str_l	str_l
+str	Nullable(String)
+\N	Nullable(String)
+str	Nullable(String)
+str_r	Nullable(String)
+str	Nullable(String)
+\N	Nullable(String)
+str_l	Nullable(String)
+str	Nullable(String)
+str_l	Nullable(String)
+str_r	Nullable(String)
+LowCardinality(String)	LowCardinality(String)	str	str	Nullable(String)	Nullable(String)	str	str
+LowCardinality(String)	LowCardinality(String)	str_r	str_r	Nullable(String)	Nullable(String)	\N	\N
+LowCardinality(String)	LowCardinality(String)	str	str	Nullable(String)	Nullable(String)	str	str
+LowCardinality(String)	LowCardinality(String)	str_r	str_r	Nullable(String)	Nullable(String)	\N	\N
+LowCardinality(String)	LowCardinality(String)	str	str	Nullable(String)	Nullable(String)	str	str
+LowCardinality(String)	LowCardinality(String)	str_r	str_r	Nullable(String)	Nullable(String)	\N	\N
+LowCardinality(String)	LowCardinality(String)			Nullable(String)	Nullable(String)	str_l	str_l
+LowCardinality(String)	LowCardinality(String)	str	str	Nullable(String)	Nullable(String)	str	str
+LowCardinality(String)	LowCardinality(String)			Nullable(String)	Nullable(String)	str_l	str_l
+LowCardinality(String)	LowCardinality(String)	str_r	str_r	Nullable(String)	Nullable(String)	\N	\N
+-- join_use_nulls --
+str	LowCardinality(Nullable(String))
+\N	LowCardinality(Nullable(String))
+str	LowCardinality(Nullable(String))
+str_r	LowCardinality(Nullable(String))
+str	LowCardinality(Nullable(String))
+\N	LowCardinality(Nullable(String))
+str_l	LowCardinality(Nullable(String))
+str	LowCardinality(Nullable(String))
+str_l	LowCardinality(Nullable(String))
+str_r	LowCardinality(Nullable(String))
+LowCardinality(String)	LowCardinality(String)	str	str	LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	str	str
+LowCardinality(String)	LowCardinality(String)	str_r	str_r	LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	\N	\N
+LowCardinality(String)	LowCardinality(String)	str	str	LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	str	str
+LowCardinality(String)	LowCardinality(String)	str_r	str_r	LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	\N	\N
+LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	str	str	LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	str	str
+LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	str_r	str_r	LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	\N	\N
+LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	\N	\N	LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	str_l	str_l
+LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	str	str	LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	str	str
+LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	\N	\N	LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	str_l	str_l
+LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	str_r	str_r	LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	\N	\N
+str	LowCardinality(Nullable(String))
+\N	LowCardinality(Nullable(String))
+str	LowCardinality(Nullable(String))
+str_r	LowCardinality(Nullable(String))
+str	LowCardinality(Nullable(String))
+\N	LowCardinality(Nullable(String))
+str_l	LowCardinality(Nullable(String))
+str	LowCardinality(Nullable(String))
+str_l	LowCardinality(Nullable(String))
+str_r	LowCardinality(Nullable(String))
+String	String	str	str	LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	str	str
+String	String	str_r	str_r	LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	\N	\N
+String	String	str	str	LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	str	str
+String	String	str_r	str_r	LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	\N	\N
+Nullable(String)	Nullable(String)	str	str	LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	str	str
+Nullable(String)	Nullable(String)	str_r	str_r	LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	\N	\N
+Nullable(String)	Nullable(String)	\N	\N	LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	str_l	str_l
+Nullable(String)	Nullable(String)	str	str	LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	str	str
+Nullable(String)	Nullable(String)	\N	\N	LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	str_l	str_l
+Nullable(String)	Nullable(String)	str_r	str_r	LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	\N	\N
+str	Nullable(String)
+\N	Nullable(String)
+str	Nullable(String)
+str_r	Nullable(String)
+str	Nullable(String)
+\N	Nullable(String)
+str_l	Nullable(String)
+str	Nullable(String)
+str_l	Nullable(String)
+str_r	Nullable(String)
+LowCardinality(String)	LowCardinality(String)	str	str	Nullable(String)	Nullable(String)	str	str
+LowCardinality(String)	LowCardinality(String)	str_r	str_r	Nullable(String)	Nullable(String)	\N	\N
+LowCardinality(String)	LowCardinality(String)	str	str	Nullable(String)	Nullable(String)	str	str
+LowCardinality(String)	LowCardinality(String)	str_r	str_r	Nullable(String)	Nullable(String)	\N	\N
+LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	str	str	Nullable(String)	Nullable(String)	str	str
+LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	str_r	str_r	Nullable(String)	Nullable(String)	\N	\N
+LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	\N	\N	Nullable(String)	Nullable(String)	str_l	str_l
+LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	str	str	Nullable(String)	Nullable(String)	str	str
+LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	\N	\N	Nullable(String)	Nullable(String)	str_l	str_l
+LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	str_r	str_r	Nullable(String)	Nullable(String)	\N	\N
+str	LowCardinality(Nullable(String))
+\N	LowCardinality(Nullable(String))
+str	LowCardinality(Nullable(String))
+str_r	LowCardinality(Nullable(String))
+str	LowCardinality(Nullable(String))
+\N	LowCardinality(Nullable(String))
+str_l	LowCardinality(Nullable(String))
+str	LowCardinality(Nullable(String))
+str_l	LowCardinality(Nullable(String))
+str_r	LowCardinality(Nullable(String))
+Nullable(String)	Nullable(String)	str	str	LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	str	str
+Nullable(String)	Nullable(String)	str_r	str_r	LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	\N	\N
+Nullable(String)	Nullable(String)	str	str	LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	str	str
+Nullable(String)	Nullable(String)	str_r	str_r	LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	\N	\N
+Nullable(String)	Nullable(String)	str	str	LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	str	str
+Nullable(String)	Nullable(String)	str_r	str_r	LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	\N	\N
+Nullable(String)	Nullable(String)	\N	\N	LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	str_l	str_l
+Nullable(String)	Nullable(String)	str	str	LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	str	str
+Nullable(String)	Nullable(String)	\N	\N	LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	str_l	str_l
+Nullable(String)	Nullable(String)	str_r	str_r	LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	\N	\N
+str	Nullable(String)
+\N	Nullable(String)
+str	Nullable(String)
+str_r	Nullable(String)
+str	Nullable(String)
+\N	Nullable(String)
+str_l	Nullable(String)
+str	Nullable(String)
+str_l	Nullable(String)
+str_r	Nullable(String)
+LowCardinality(String)	LowCardinality(String)	str	str	Nullable(String)	Nullable(String)	str	str
+LowCardinality(String)	LowCardinality(String)	str_r	str_r	Nullable(String)	Nullable(String)	\N	\N
+LowCardinality(String)	LowCardinality(String)	str	str	Nullable(String)	Nullable(String)	str	str
+LowCardinality(String)	LowCardinality(String)	str_r	str_r	Nullable(String)	Nullable(String)	\N	\N
+LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	str	str	Nullable(String)	Nullable(String)	str	str
+LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	str_r	str_r	Nullable(String)	Nullable(String)	\N	\N
+LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	\N	\N	Nullable(String)	Nullable(String)	str_l	str_l
+LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	str	str	Nullable(String)	Nullable(String)	str	str
+LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	\N	\N	Nullable(String)	Nullable(String)	str_l	str_l
+LowCardinality(Nullable(String))	LowCardinality(Nullable(String))	str_r	str_r	Nullable(String)	Nullable(String)	\N	\N
diff --git a/tests/queries/0_stateless/01049_join_low_card_bug.sql b/tests/queries/0_stateless/01049_join_low_card_bug.sql
index 39427c962fa..ba245c2eba6 100644
--- a/tests/queries/0_stateless/01049_join_low_card_bug.sql
+++ b/tests/queries/0_stateless/01049_join_low_card_bug.sql
@@ -20,6 +20,135 @@ INSERT INTO l VALUES (0, 'str'), (2, 'str_l');
 INSERT INTO nl VALUES (0, 'str'), (2, 'str_l');
 INSERT INTO l_lc VALUES (0, 'str'), (2, 'str_l');
 
+
+SET join_use_nulls = 0;
+
+--
+
+SELECT lc, toTypeName(lc) FROM l_lc AS l RIGHT JOIN r_lc AS r USING (x) ORDER BY x;
+SELECT lc, toTypeName(lc) FROM l_lc AS l RIGHT JOIN r_lc AS r USING (lc) ORDER BY x;
+SELECT lc, toTypeName(lc) FROM l_lc AS l FULL JOIN r_lc AS r USING (x) ORDER BY x;
+SELECT lc, toTypeName(lc) FROM l_lc AS l FULL JOIN r_lc AS r USING (lc) ORDER BY x;
+
+SELECT toTypeName(r.lc), toTypeName(materialize(r.lc)), r.lc, materialize(r.lc), toTypeName(l.lc), toTypeName(materialize(l.lc)), l.lc, materialize(l.lc) FROM l_lc AS l RIGHT JOIN r_lc AS r USING (x) ORDER BY x;
+SELECT toTypeName(r.lc), toTypeName(materialize(r.lc)), r.lc, materialize(r.lc), toTypeName(l.lc), toTypeName(materialize(l.lc)), l.lc, materialize(l.lc) FROM l_lc AS l RIGHT JOIN r_lc AS r USING (lc) ORDER BY x;
+SELECT toTypeName(r.lc), toTypeName(materialize(r.lc)), r.lc, materialize(r.lc), toTypeName(l.lc), toTypeName(materialize(l.lc)), l.lc, materialize(l.lc) FROM l_lc AS l FULL JOIN r_lc AS r USING (x) ORDER BY x;
+SELECT toTypeName(r.lc), toTypeName(materialize(r.lc)), r.lc, materialize(r.lc), toTypeName(l.lc), toTypeName(materialize(l.lc)), l.lc, materialize(l.lc) FROM l_lc AS l FULL JOIN r_lc AS r USING (lc) ORDER BY x;
+
+--
+
+SELECT lc, toTypeName(lc) FROM l_lc AS l RIGHT JOIN r USING (x) ORDER BY x;
+SELECT lc, toTypeName(lc) FROM l_lc AS l RIGHT JOIN r USING (lc) ORDER BY x;
+SELECT lc, toTypeName(lc) FROM l_lc AS l FULL JOIN r USING (x) ORDER BY x;
+SELECT lc, toTypeName(lc) FROM l_lc AS l FULL JOIN r USING (lc) ORDER BY x;
+
+SELECT toTypeName(r.lc), toTypeName(materialize(r.lc)), r.lc, materialize(r.lc), toTypeName(l.lc), toTypeName(materialize(l.lc)), l.lc, materialize(l.lc) FROM l_lc AS l RIGHT JOIN r USING (x) ORDER BY x;
+SELECT toTypeName(r.lc), toTypeName(materialize(r.lc)), r.lc, materialize(r.lc), toTypeName(l.lc), toTypeName(materialize(l.lc)), l.lc, materialize(l.lc) FROM l_lc AS l RIGHT JOIN r USING (lc) ORDER BY x;
+SELECT toTypeName(r.lc), toTypeName(materialize(r.lc)), r.lc, materialize(r.lc), toTypeName(l.lc), toTypeName(materialize(l.lc)), l.lc, materialize(l.lc) FROM l_lc AS l FULL JOIN r USING (x) ORDER BY x;
+SELECT toTypeName(r.lc), toTypeName(materialize(r.lc)), r.lc, materialize(r.lc), toTypeName(l.lc), toTypeName(materialize(l.lc)), l.lc, materialize(l.lc) FROM l_lc AS l FULL JOIN r USING (lc) ORDER BY x;
+
+--
+
+SELECT lc, toTypeName(lc) FROM l RIGHT JOIN r USING (x) ORDER BY x;
+SELECT lc, toTypeName(lc) FROM l RIGHT JOIN r USING (lc) ORDER BY x;
+SELECT lc, toTypeName(lc) FROM l FULL JOIN r USING (x) ORDER BY x;
+SELECT lc, toTypeName(lc) FROM l FULL JOIN r USING (lc) ORDER BY x;
+
+SELECT toTypeName(r.lc), toTypeName(materialize(r.lc)), r.lc, materialize(r.lc), toTypeName(l.lc), toTypeName(materialize(l.lc)), l.lc, materialize(l.lc) FROM l RIGHT JOIN r_lc AS r USING (x) ORDER BY x;
+SELECT toTypeName(r.lc), toTypeName(materialize(r.lc)), r.lc, materialize(r.lc), toTypeName(l.lc), toTypeName(materialize(l.lc)), l.lc, materialize(l.lc) FROM l RIGHT JOIN r_lc AS r USING (lc) ORDER BY x;
+SELECT toTypeName(r.lc), toTypeName(materialize(r.lc)), r.lc, materialize(r.lc), toTypeName(l.lc), toTypeName(materialize(l.lc)), l.lc, materialize(l.lc) FROM l FULL JOIN r_lc AS r USING (x) ORDER BY x;
+SELECT toTypeName(r.lc), toTypeName(materialize(r.lc)), r.lc, materialize(r.lc), toTypeName(l.lc), toTypeName(materialize(l.lc)), l.lc, materialize(l.lc) FROM l FULL JOIN r_lc AS r USING (lc) ORDER BY x;
+
+--
+
+SELECT lc, toTypeName(lc) FROM l_lc RIGHT JOIN nr USING (x) ORDER BY x;
+SELECT lc, toTypeName(lc) FROM l_lc RIGHT JOIN nr USING (lc) ORDER BY x;
+SELECT lc, toTypeName(lc) FROM l_lc FULL JOIN nr USING (x) ORDER BY x;
+SELECT lc, toTypeName(lc) FROM l_lc FULL JOIN nr USING (lc) ORDER BY x;
+
+SELECT toTypeName(r.lc), toTypeName(materialize(r.lc)), r.lc, materialize(r.lc), toTypeName(l.lc), toTypeName(materialize(l.lc)), l.lc, materialize(l.lc) FROM l_lc AS l RIGHT JOIN nr AS r USING (x) ORDER BY x;
+SELECT toTypeName(r.lc), toTypeName(materialize(r.lc)), r.lc, materialize(r.lc), toTypeName(l.lc), toTypeName(materialize(l.lc)), l.lc, materialize(l.lc) FROM l_lc AS l RIGHT JOIN nr AS r USING (lc) ORDER BY x;
+SELECT toTypeName(r.lc), toTypeName(materialize(r.lc)), r.lc, materialize(r.lc), toTypeName(l.lc), toTypeName(materialize(l.lc)), l.lc, materialize(l.lc) FROM l_lc AS l FULL JOIN nr AS r USING (x) ORDER BY x;
+SELECT toTypeName(r.lc), toTypeName(materialize(r.lc)), r.lc, materialize(r.lc), toTypeName(l.lc), toTypeName(materialize(l.lc)), l.lc, materialize(l.lc) FROM l_lc AS l FULL JOIN nr AS r USING (lc) ORDER BY x;
+
+--
+
+SELECT lc, toTypeName(lc) FROM nl RIGHT JOIN r_lc USING (x) ORDER BY x;
+SELECT lc, toTypeName(lc) FROM nl RIGHT JOIN r_lc USING (lc) ORDER BY x;
+SELECT lc, toTypeName(lc) FROM nl FULL JOIN r_lc USING (x) ORDER BY x;
+SELECT lc, toTypeName(lc) FROM nl FULL JOIN r_lc USING (lc) ORDER BY x;
+
+SELECT toTypeName(r.lc), toTypeName(materialize(r.lc)), r.lc, materialize(r.lc), toTypeName(l.lc), toTypeName(materialize(l.lc)), l.lc, materialize(l.lc) FROM nl AS l RIGHT JOIN r_lc AS r USING (x) ORDER BY x;
+SELECT toTypeName(r.lc), toTypeName(materialize(r.lc)), r.lc, materialize(r.lc), toTypeName(l.lc), toTypeName(materialize(l.lc)), l.lc, materialize(l.lc) FROM nl AS l RIGHT JOIN r_lc AS r USING (lc) ORDER BY x;
+SELECT toTypeName(r.lc), toTypeName(materialize(r.lc)), r.lc, materialize(r.lc), toTypeName(l.lc), toTypeName(materialize(l.lc)), l.lc, materialize(l.lc) FROM nl AS l FULL JOIN r_lc AS r USING (x) ORDER BY x;
+SELECT toTypeName(r.lc), toTypeName(materialize(r.lc)), r.lc, materialize(r.lc), toTypeName(l.lc), toTypeName(materialize(l.lc)), l.lc, materialize(l.lc) FROM nl AS l FULL JOIN r_lc AS r USING (lc) ORDER BY x;
+
+SELECT '-- join_use_nulls --';
+
+SET join_use_nulls = 1;
+
+SELECT lc, toTypeName(lc) FROM l_lc AS l RIGHT JOIN r_lc AS r USING (x) ORDER BY x;
+SELECT lc, toTypeName(lc) FROM l_lc AS l RIGHT JOIN r_lc AS r USING (lc) ORDER BY x;
+SELECT lc, toTypeName(lc) FROM l_lc AS l FULL JOIN r_lc AS r USING (x) ORDER BY x;
+SELECT lc, toTypeName(lc) FROM l_lc AS l FULL JOIN r_lc AS r USING (lc) ORDER BY x;
+
+SELECT toTypeName(r.lc), toTypeName(materialize(r.lc)), r.lc, materialize(r.lc), toTypeName(l.lc), toTypeName(materialize(l.lc)), l.lc, materialize(l.lc) FROM l_lc AS l RIGHT JOIN r_lc AS r USING (x) ORDER BY x;
+SELECT toTypeName(r.lc), toTypeName(materialize(r.lc)), r.lc, materialize(r.lc), toTypeName(l.lc), toTypeName(materialize(l.lc)), l.lc, materialize(l.lc) FROM l_lc AS l RIGHT JOIN r_lc AS r USING (lc) ORDER BY x;
+SELECT toTypeName(r.lc), toTypeName(materialize(r.lc)), r.lc, materialize(r.lc), toTypeName(l.lc), toTypeName(materialize(l.lc)), l.lc, materialize(l.lc) FROM l_lc AS l FULL JOIN r_lc AS r USING (x) ORDER BY x;
+SELECT toTypeName(r.lc), toTypeName(materialize(r.lc)), r.lc, materialize(r.lc), toTypeName(l.lc), toTypeName(materialize(l.lc)), l.lc, materialize(l.lc) FROM l_lc AS l FULL JOIN r_lc AS r USING (lc) ORDER BY x;
+
+--
+
+SELECT lc, toTypeName(lc) FROM l_lc AS l RIGHT JOIN r USING (x) ORDER BY x;
+SELECT lc, toTypeName(lc) FROM l_lc AS l RIGHT JOIN r USING (lc) ORDER BY x;
+SELECT lc, toTypeName(lc) FROM l_lc AS l FULL JOIN r USING (x) ORDER BY x;
+SELECT lc, toTypeName(lc) FROM l_lc AS l FULL JOIN r USING (lc) ORDER BY x;
+
+SELECT toTypeName(r.lc), toTypeName(materialize(r.lc)), r.lc, materialize(r.lc), toTypeName(l.lc), toTypeName(materialize(l.lc)), l.lc, materialize(l.lc) FROM l_lc AS l RIGHT JOIN r USING (x) ORDER BY x;
+SELECT toTypeName(r.lc), toTypeName(materialize(r.lc)), r.lc, materialize(r.lc), toTypeName(l.lc), toTypeName(materialize(l.lc)), l.lc, materialize(l.lc) FROM l_lc AS l RIGHT JOIN r USING (lc) ORDER BY x;
+SELECT toTypeName(r.lc), toTypeName(materialize(r.lc)), r.lc, materialize(r.lc), toTypeName(l.lc), toTypeName(materialize(l.lc)), l.lc, materialize(l.lc) FROM l_lc AS l FULL JOIN r USING (x) ORDER BY x;
+SELECT toTypeName(r.lc), toTypeName(materialize(r.lc)), r.lc, materialize(r.lc), toTypeName(l.lc), toTypeName(materialize(l.lc)), l.lc, materialize(l.lc) FROM l_lc AS l FULL JOIN r USING (lc) ORDER BY x;
+
+--
+
+SELECT lc, toTypeName(lc) FROM l RIGHT JOIN r USING (x) ORDER BY x;
+SELECT lc, toTypeName(lc) FROM l RIGHT JOIN r USING (lc) ORDER BY x;
+SELECT lc, toTypeName(lc) FROM l FULL JOIN r USING (x) ORDER BY x;
+SELECT lc, toTypeName(lc) FROM l FULL JOIN r USING (lc) ORDER BY x;
+
+SELECT toTypeName(r.lc), toTypeName(materialize(r.lc)), r.lc, materialize(r.lc), toTypeName(l.lc), toTypeName(materialize(l.lc)), l.lc, materialize(l.lc) FROM l RIGHT JOIN r_lc AS r USING (x) ORDER BY x;
+SELECT toTypeName(r.lc), toTypeName(materialize(r.lc)), r.lc, materialize(r.lc), toTypeName(l.lc), toTypeName(materialize(l.lc)), l.lc, materialize(l.lc) FROM l RIGHT JOIN r_lc AS r USING (lc) ORDER BY x;
+SELECT toTypeName(r.lc), toTypeName(materialize(r.lc)), r.lc, materialize(r.lc), toTypeName(l.lc), toTypeName(materialize(l.lc)), l.lc, materialize(l.lc) FROM l FULL JOIN r_lc AS r USING (x) ORDER BY x;
+SELECT toTypeName(r.lc), toTypeName(materialize(r.lc)), r.lc, materialize(r.lc), toTypeName(l.lc), toTypeName(materialize(l.lc)), l.lc, materialize(l.lc) FROM l FULL JOIN r_lc AS r USING (lc) ORDER BY x;
+
+--
+
+SELECT lc, toTypeName(lc) FROM l_lc RIGHT JOIN nr USING (x) ORDER BY x;
+SELECT lc, toTypeName(lc) FROM l_lc RIGHT JOIN nr USING (lc) ORDER BY x;
+SELECT lc, toTypeName(lc) FROM l_lc FULL JOIN nr USING (x) ORDER BY x;
+SELECT lc, toTypeName(lc) FROM l_lc FULL JOIN nr USING (lc) ORDER BY x;
+
+SELECT toTypeName(r.lc), toTypeName(materialize(r.lc)), r.lc, materialize(r.lc), toTypeName(l.lc), toTypeName(materialize(l.lc)), l.lc, materialize(l.lc) FROM l_lc AS l RIGHT JOIN nr AS r USING (x) ORDER BY x;
+SELECT toTypeName(r.lc), toTypeName(materialize(r.lc)), r.lc, materialize(r.lc), toTypeName(l.lc), toTypeName(materialize(l.lc)), l.lc, materialize(l.lc) FROM l_lc AS l RIGHT JOIN nr AS r USING (lc) ORDER BY x;
+SELECT toTypeName(r.lc), toTypeName(materialize(r.lc)), r.lc, materialize(r.lc), toTypeName(l.lc), toTypeName(materialize(l.lc)), l.lc, materialize(l.lc) FROM l_lc AS l FULL JOIN nr AS r USING (x) ORDER BY x;
+SELECT toTypeName(r.lc), toTypeName(materialize(r.lc)), r.lc, materialize(r.lc), toTypeName(l.lc), toTypeName(materialize(l.lc)), l.lc, materialize(l.lc) FROM l_lc AS l FULL JOIN nr AS r USING (lc) ORDER BY x;
+
+--
+
+SELECT lc, toTypeName(lc) FROM nl RIGHT JOIN r_lc USING (x) ORDER BY x;
+SELECT lc, toTypeName(lc) FROM nl RIGHT JOIN r_lc USING (lc) ORDER BY x;
+SELECT lc, toTypeName(lc) FROM nl FULL JOIN r_lc USING (x) ORDER BY x;
+SELECT lc, toTypeName(lc) FROM nl FULL JOIN r_lc USING (lc) ORDER BY x;
+
+SELECT toTypeName(r.lc), toTypeName(materialize(r.lc)), r.lc, materialize(r.lc), toTypeName(l.lc), toTypeName(materialize(l.lc)), l.lc, materialize(l.lc) FROM nl AS l RIGHT JOIN r_lc AS r USING (x) ORDER BY x;
+SELECT toTypeName(r.lc), toTypeName(materialize(r.lc)), r.lc, materialize(r.lc), toTypeName(l.lc), toTypeName(materialize(l.lc)), l.lc, materialize(l.lc) FROM nl AS l RIGHT JOIN r_lc AS r USING (lc) ORDER BY x;
+SELECT toTypeName(r.lc), toTypeName(materialize(r.lc)), r.lc, materialize(r.lc), toTypeName(l.lc), toTypeName(materialize(l.lc)), l.lc, materialize(l.lc) FROM nl AS l FULL JOIN r_lc AS r USING (x) ORDER BY x;
+SELECT toTypeName(r.lc), toTypeName(materialize(r.lc)), r.lc, materialize(r.lc), toTypeName(l.lc), toTypeName(materialize(l.lc)), l.lc, materialize(l.lc) FROM nl AS l FULL JOIN r_lc AS r USING (lc) ORDER BY x;
+
+set join_algorithm = 'partial_merge';
+
+SET join_use_nulls = 0;
+
 --
 
 SELECT lc, toTypeName(lc) FROM l_lc AS l RIGHT JOIN r_lc AS r USING (x) ORDER BY x;