Merge pull request ClickHouse#79035 from yariks5s/check_rows_while_dispatching_blocks

Minor: Do not add empty blocks to join while using ConcurrentHashJoin

Author: yariks5s

src/Interpreters/ConcurrentHashJoin.cpp

@@ -251,7 +251,7 @@ bool ConcurrentHashJoin::addBlockToJoin(const Block & right_block_, bool check_l
     size_t blocks_left = 0;
     for (const auto & block : dispatched_blocks)
     {
-        if (block)
+        if (block.rows())
         {
             ++blocks_left;
         }
@@ -265,7 +265,7 @@ bool ConcurrentHashJoin::addBlockToJoin(const Block & right_block_, bool check_l
             auto & hash_join = hash_joins[i];
             auto & dispatched_block = dispatched_blocks[i];
 
-            if (dispatched_block)
+            if (dispatched_block.rows())
             {
                 /// if current hash_join is already processed by another thread, skip it and try later
                 std::unique_lock<std::mutex> lock(hash_join->mutex, std::try_to_lock);