do not affect other SquashingBlockInputStream instances

dbms/src/DataStreams/SquashingBlockInputStream.cpp

@@ -5,8 +5,8 @@ namespace DB
 {
 
 SquashingBlockInputStream::SquashingBlockInputStream(
-    const BlockInputStreamPtr & src, size_t min_block_size_rows, size_t min_block_size_bytes)
-    : header(src->getHeader()), transform(min_block_size_rows, min_block_size_bytes, true)
+    const BlockInputStreamPtr & src, size_t min_block_size_rows, size_t min_block_size_bytes, bool reserve_memory)
+    : header(src->getHeader()), transform(min_block_size_rows, min_block_size_bytes, reserve_memory)
 {
     children.emplace_back(src);
 }

dbms/src/DataStreams/SquashingBlockInputStream.h

@@ -12,7 +12,8 @@ namespace DB
 class SquashingBlockInputStream : public IBlockInputStream
 {
 public:
-    SquashingBlockInputStream(const BlockInputStreamPtr & src, size_t min_block_size_rows, size_t min_block_size_bytes);
+    SquashingBlockInputStream(const BlockInputStreamPtr & src, size_t min_block_size_rows, size_t min_block_size_bytes,
+                              bool reserve_memory = false);
 
     String getName() const override { return "Squashing"; }
 

dbms/src/Interpreters/InterpreterSelectQuery.cpp

@@ -1122,7 +1122,7 @@ void InterpreterSelectQuery::executeImpl(TPipeline & pipeline, const BlockInputS
                     {
                         if (size_t rows_in_block = settings.partial_merge_join_rows_in_left_blocks)
                             for (auto & stream : pipeline.streams)
-                                stream = std::make_shared<SquashingBlockInputStream>(stream, rows_in_block, 0);
+                                stream = std::make_shared<SquashingBlockInputStream>(stream, rows_in_block, 0, true);
                     }
                 }