diff --git a/docs/en/interfaces/third-party/client-libraries.md b/docs/en/interfaces/third-party/client-libraries.md
index f7603994163..e229198bdfd 100644
--- a/docs/en/interfaces/third-party/client-libraries.md
+++ b/docs/en/interfaces/third-party/client-libraries.md
@@ -2,6 +2,7 @@
 slug: /en/interfaces/third-party/client-libraries
 sidebar_position: 26
 sidebar_label: Client Libraries
+description: Third-party client libraries
 ---
 
 # Client Libraries from Third-party Developers
@@ -10,68 +11,68 @@ sidebar_label: Client Libraries
 ClickHouse Inc does **not** maintain the libraries listed below and hasn’t done any extensive testing to ensure their quality.
 :::
 
-- Python
-    - [infi.clickhouse_orm](https://github.com/Infinidat/infi.clickhouse_orm)
-    - [clickhouse-driver](https://github.com/mymarilyn/clickhouse-driver)
-    - [clickhouse-client](https://github.com/yurial/clickhouse-client)
-    - [aiochclient](https://github.com/maximdanilchenko/aiochclient)
-    - [asynch](https://github.com/long2ice/asynch)
-- PHP
-    - [smi2/phpclickhouse](https://packagist.org/packages/smi2/phpClickHouse)
-    - [8bitov/clickhouse-php-client](https://packagist.org/packages/8bitov/clickhouse-php-client)
-    - [bozerkins/clickhouse-client](https://packagist.org/packages/bozerkins/clickhouse-client)
-    - [simpod/clickhouse-client](https://packagist.org/packages/simpod/clickhouse-client)
-    - [seva-code/php-click-house-client](https://packagist.org/packages/seva-code/php-click-house-client)
-    - [SeasClick C++ client](https://github.com/SeasX/SeasClick)
-    - [one-ck](https://github.com/lizhichao/one-ck)
-    - [glushkovds/phpclickhouse-laravel](https://packagist.org/packages/glushkovds/phpclickhouse-laravel)
-    - [kolya7k ClickHouse PHP extension](https://github.com//kolya7k/clickhouse-php)
-    - [hyvor/clickhouse-php](https://github.com/hyvor/clickhouse-php)
-- Go
-    - [clickhouse](https://github.com/kshvakov/clickhouse/)
-    - [go-clickhouse](https://github.com/roistat/go-clickhouse)
-    - [chconn](https://github.com/vahid-sohrabloo/chconn)
-    - [mailrugo-clickhouse](https://github.com/mailru/go-clickhouse)
-    - [golang-clickhouse](https://github.com/leprosus/golang-clickhouse)
-    - [uptrace/go-clickhouse](https://clickhouse.uptrace.dev/)
-- Swift
-    - [ClickHouseNIO](https://github.com/patrick-zippenfenig/ClickHouseNIO)
-    - [ClickHouseVapor ORM](https://github.com/patrick-zippenfenig/ClickHouseVapor)
-- NodeJs
-    - [clickhouse (NodeJs)](https://github.com/TimonKK/clickhouse)
-    - [node-clickhouse](https://github.com/apla/node-clickhouse)
-    - [nestjs-clickhouse](https://github.com/depyronick/nestjs-clickhouse)
-    - [clickhouse-client](https://github.com/depyronick/clickhouse-client)
-    - [node-clickhouse-orm](https://github.com/zimv/node-clickhouse-orm)
-- Perl
-    - [perl-DBD-ClickHouse](https://github.com/elcamlost/perl-DBD-ClickHouse)
-    - [HTTP-ClickHouse](https://metacpan.org/release/HTTP-ClickHouse)
-    - [AnyEvent-ClickHouse](https://metacpan.org/release/AnyEvent-ClickHouse)
-- Ruby
-    - [ClickHouse (Ruby)](https://github.com/shlima/click_house)
-    - [clickhouse-activerecord](https://github.com/PNixx/clickhouse-activerecord)
-- Rust
-    - [clickhouse.rs](https://github.com/loyd/clickhouse.rs)
-    - [clickhouse-rs](https://github.com/suharev7/clickhouse-rs)
-    - [Klickhouse](https://github.com/Protryon/klickhouse)
-- R
-    - [RClickHouse](https://github.com/IMSMWU/RClickHouse)
-- Java
-    - [clickhouse-client-java](https://github.com/VirtusAI/clickhouse-client-java)
-    - [clickhouse-client](https://github.com/Ecwid/clickhouse-client)
-- Scala
-    - [clickhouse-scala-client](https://github.com/crobox/clickhouse-scala-client)
-- Kotlin
-    - [AORM](https://github.com/TanVD/AORM)
-- C#
-    - [Octonica.ClickHouseClient](https://github.com/Octonica/ClickHouseClient)
-    - [ClickHouse.Ado](https://github.com/killwort/ClickHouse-Net)
-    - [ClickHouse.Client](https://github.com/DarkWanderer/ClickHouse.Client)
-    - [ClickHouse.Net](https://github.com/ilyabreev/ClickHouse.Net)
-- Elixir
-    - [clickhousex](https://github.com/appodeal/clickhousex/)
-    - [pillar](https://github.com/sofakingworld/pillar)
-- Nim
-    - [nim-clickhouse](https://github.com/leonardoce/nim-clickhouse)
-- Haskell
-    - [hdbc-clickhouse](https://github.com/zaneli/hdbc-clickhouse)
+### Python
+ - [infi.clickhouse_orm](https://github.com/Infinidat/infi.clickhouse_orm)
+ - [clickhouse-driver](https://github.com/mymarilyn/clickhouse-driver)
+ - [clickhouse-client](https://github.com/yurial/clickhouse-client)
+ - [aiochclient](https://github.com/maximdanilchenko/aiochclient)
+ - [asynch](https://github.com/long2ice/asynch)
+### PHP
+ - [smi2/phpclickhouse](https://packagist.org/packages/smi2/phpClickHouse)
+ - [8bitov/clickhouse-php-client](https://packagist.org/packages/8bitov/clickhouse-php-client)
+ - [bozerkins/clickhouse-client](https://packagist.org/packages/bozerkins/clickhouse-client)
+ - [simpod/clickhouse-client](https://packagist.org/packages/simpod/clickhouse-client)
+ - [seva-code/php-click-house-client](https://packagist.org/packages/seva-code/php-click-house-client)
+ - [SeasClick C++ client](https://github.com/SeasX/SeasClick)
+ - [one-ck](https://github.com/lizhichao/one-ck)
+ - [glushkovds/phpclickhouse-laravel](https://packagist.org/packages/glushkovds/phpclickhouse-laravel)
+ - [kolya7k ClickHouse PHP extension](https://github.com//kolya7k/clickhouse-php)
+ - [hyvor/clickhouse-php](https://github.com/hyvor/clickhouse-php)
+### Go
+ - [clickhouse](https://github.com/kshvakov/clickhouse/)
+ - [go-clickhouse](https://github.com/roistat/go-clickhouse)
+ - [chconn](https://github.com/vahid-sohrabloo/chconn)
+ - [mailrugo-clickhouse](https://github.com/mailru/go-clickhouse)
+ - [golang-clickhouse](https://github.com/leprosus/golang-clickhouse)
+ - [uptrace/go-clickhouse](https://clickhouse.uptrace.dev/)
+### Swift
+ - [ClickHouseNIO](https://github.com/patrick-zippenfenig/ClickHouseNIO)
+ - [ClickHouseVapor ORM](https://github.com/patrick-zippenfenig/ClickHouseVapor)
+### NodeJs
+ - [clickhouse (NodeJs)](https://github.com/TimonKK/clickhouse)
+ - [node-clickhouse](https://github.com/apla/node-clickhouse)
+ - [nestjs-clickhouse](https://github.com/depyronick/nestjs-clickhouse)
+ - [clickhouse-client](https://github.com/depyronick/clickhouse-client)
+ - [node-clickhouse-orm](https://github.com/zimv/node-clickhouse-orm)
+### Perl
+ - [perl-DBD-ClickHouse](https://github.com/elcamlost/perl-DBD-ClickHouse)
+ - [HTTP-ClickHouse](https://metacpan.org/release/HTTP-ClickHouse)
+ - [AnyEvent-ClickHouse](https://metacpan.org/release/AnyEvent-ClickHouse)
+### Ruby
+ - [ClickHouse (Ruby)](https://github.com/shlima/click_house)
+ - [clickhouse-activerecord](https://github.com/PNixx/clickhouse-activerecord)
+### Rust
+ - [clickhouse.rs](https://github.com/loyd/clickhouse.rs)
+ - [clickhouse-rs](https://github.com/suharev7/clickhouse-rs)
+ - [Klickhouse](https://github.com/Protryon/klickhouse)
+### R
+ - [RClickHouse](https://github.com/IMSMWU/RClickHouse)
+### Java
+ - [clickhouse-client-java](https://github.com/VirtusAI/clickhouse-client-java)
+ - [clickhouse-client](https://github.com/Ecwid/clickhouse-client)
+### Scala
+ - [clickhouse-scala-client](https://github.com/crobox/clickhouse-scala-client)
+### Kotlin
+ - [AORM](https://github.com/TanVD/AORM)
+### C#
+ - [Octonica.ClickHouseClient](https://github.com/Octonica/ClickHouseClient)
+ - [ClickHouse.Ado](https://github.com/killwort/ClickHouse-Net)
+ - [ClickHouse.Client](https://github.com/DarkWanderer/ClickHouse.Client)
+ - [ClickHouse.Net](https://github.com/ilyabreev/ClickHouse.Net)
+### Elixir
+ - [clickhousex](https://github.com/appodeal/clickhousex/)
+ - [pillar](https://github.com/sofakingworld/pillar)
+### Nim
+ - [nim-clickhouse](https://github.com/leonardoce/nim-clickhouse)
+### Haskell
+ - [hdbc-clickhouse](https://github.com/zaneli/hdbc-clickhouse)
diff --git a/src/Processors/QueryPlan/IQueryPlanStep.h b/src/Processors/QueryPlan/IQueryPlanStep.h
index a608c6f8058..df5c13a7f3b 100644
--- a/src/Processors/QueryPlan/IQueryPlanStep.h
+++ b/src/Processors/QueryPlan/IQueryPlanStep.h
@@ -16,6 +16,11 @@ using Processors = std::vector<ProcessorPtr>;
 
 namespace JSONBuilder { class JSONMap; }
 
+namespace ErrorCodes
+{
+    extern const int NOT_IMPLEMENTED;
+}
+
 /// Description of data stream.
 /// Single logical data stream may relate to many ports of pipeline.
 class DataStream
@@ -107,7 +112,30 @@ public:
     /// Append extra processors for this step.
     void appendExtraProcessors(const Processors & extra_processors);
 
+    /// Updates the input streams of the given step. Used during query plan optimizations.
+    /// It won't do any validation of new streams, so it is your responsibility to ensure that this update doesn't break anything
+    /// (e.g. you update data stream traits or correctly remove / add columns).
+    void updateInputStreams(DataStreams input_streams_)
+    {
+        chassert(canUpdateInputStream());
+        input_streams = std::move(input_streams_);
+        updateOutputStream();
+    }
+
+    void updateInputStream(DataStream input_stream) { updateInputStreams(DataStreams{input_stream}); }
+
+    void updateInputStream(DataStream input_stream, size_t idx)
+    {
+        chassert(canUpdateInputStream() && idx < input_streams.size());
+        input_streams[idx] = input_stream;
+        updateOutputStream();
+    }
+
+    virtual bool canUpdateInputStream() const { return false; }
+
 protected:
+    virtual void updateOutputStream() { throw Exception(ErrorCodes::NOT_IMPLEMENTED, "Not implemented"); }
+
     DataStreams input_streams;
     std::optional<DataStream> output_stream;
 
diff --git a/src/Processors/QueryPlan/ITransformingStep.h b/src/Processors/QueryPlan/ITransformingStep.h
index 77de668fbdb..32bf3b6af90 100644
--- a/src/Processors/QueryPlan/ITransformingStep.h
+++ b/src/Processors/QueryPlan/ITransformingStep.h
@@ -55,17 +55,6 @@ public:
     const TransformTraits & getTransformTraits() const { return transform_traits; }
     const DataStreamTraits & getDataStreamTraits() const { return data_stream_traits; }
 
-    /// Updates the input stream of the given step. Used during query plan optimizations.
-    /// It won't do any validation of a new stream, so it is your responsibility to ensure that this update doesn't break anything
-    /// (e.g. you update data stream traits or correctly remove / add columns).
-    void updateInputStream(DataStream input_stream)
-    {
-        input_streams.clear();
-        input_streams.emplace_back(std::move(input_stream));
-
-        updateOutputStream();
-    }
-
     void describePipeline(FormatSettings & settings) const override;
 
     /// Enforcement is supposed to be done through the special settings that will be taken into account by remote nodes during query planning (e.g. force_aggregation_in_order).
@@ -75,6 +64,8 @@ public:
         throw Exception(ErrorCodes::NOT_IMPLEMENTED, "Not implemented");
     }
 
+    bool canUpdateInputStream() const override { return true; }
+
 protected:
     /// Create output stream from header and traits.
     static DataStream createOutputStream(
@@ -85,8 +76,6 @@ protected:
     TransformTraits transform_traits;
 
 private:
-    virtual void updateOutputStream() = 0;
-
     /// If we should collect processors got after pipeline transformation.
     bool collect_processors;
 
diff --git a/src/Processors/QueryPlan/JoinStep.cpp b/src/Processors/QueryPlan/JoinStep.cpp
index 63a5eeb51d2..9ac0f18d2c3 100644
--- a/src/Processors/QueryPlan/JoinStep.cpp
+++ b/src/Processors/QueryPlan/JoinStep.cpp
@@ -24,11 +24,7 @@ JoinStep::JoinStep(
     bool keep_left_read_in_order_)
     : join(std::move(join_)), max_block_size(max_block_size_), max_streams(max_streams_), keep_left_read_in_order(keep_left_read_in_order_)
 {
-    input_streams = {left_stream_, right_stream_};
-    output_stream = DataStream
-    {
-        .header = JoiningTransform::transformHeader(left_stream_.header, join),
-    };
+    updateInputStreams(DataStreams{left_stream_, right_stream_});
 }
 
 QueryPipelineBuilderPtr JoinStep::updatePipeline(QueryPipelineBuilders pipelines, const BuildQueryPipelineSettings &)
@@ -95,20 +91,12 @@ void JoinStep::describeActions(JSONBuilder::JSONMap & map) const
         map.add("Clauses", table_join.formatClauses(table_join.getClauses(), true /*short_format*/));
 }
 
-void JoinStep::updateInputStream(const DataStream & new_input_stream_, size_t idx)
+void JoinStep::updateOutputStream()
 {
-    if (idx == 0)
+    output_stream = DataStream
     {
-        input_streams = {new_input_stream_, input_streams.at(1)};
-        output_stream = DataStream
-        {
-            .header = JoiningTransform::transformHeader(new_input_stream_.header, join),
-        };
-    }
-    else
-    {
-        input_streams = {input_streams.at(0), new_input_stream_};
-    }
+        .header = JoiningTransform::transformHeader(input_streams[0].header, join),
+    };
 }
 
 static ITransformingStep::Traits getStorageJoinTraits()
diff --git a/src/Processors/QueryPlan/JoinStep.h b/src/Processors/QueryPlan/JoinStep.h
index 369ee9bec8b..5bfaa41f9b6 100644
--- a/src/Processors/QueryPlan/JoinStep.h
+++ b/src/Processors/QueryPlan/JoinStep.h
@@ -33,9 +33,11 @@ public:
     const JoinPtr & getJoin() const { return join; }
     bool allowPushDownToRight() const;
 
-    void updateInputStream(const DataStream & new_input_stream_, size_t idx);
+    bool canUpdateInputStream() const override { return true; }
 
 private:
+    void updateOutputStream() override;
+
     JoinPtr join;
     size_t max_block_size;
     size_t max_streams;
diff --git a/src/Processors/QueryPlan/QueryPlan.cpp b/src/Processors/QueryPlan/QueryPlan.cpp
index 5d38bfb42c4..ec82c233ce4 100644
--- a/src/Processors/QueryPlan/QueryPlan.cpp
+++ b/src/Processors/QueryPlan/QueryPlan.cpp
@@ -460,16 +460,24 @@ static void updateDataStreams(QueryPlan::Node & root)
 
         static bool visitTopDownImpl(QueryPlan::Node * /*current_node*/, QueryPlan::Node * /*parent_node*/) { return true; }
 
-        static void visitBottomUpImpl(QueryPlan::Node * current_node, QueryPlan::Node * parent_node)
+        static void visitBottomUpImpl(QueryPlan::Node * current_node, QueryPlan::Node * /*parent_node*/)
         {
-            if (!parent_node || parent_node->children.size() != 1)
+            auto & current_step = *current_node->step;
+            if (!current_step.canUpdateInputStream() || current_node->children.empty())
                 return;
 
-            if (!current_node->step->hasOutputStream())
-                return;
+            for (const auto * child : current_node->children)
+            {
+                if (!child->step->hasOutputStream())
+                    return;
+            }
 
-            if (auto * parent_transform_step = dynamic_cast<ITransformingStep *>(parent_node->step.get()); parent_transform_step)
-                parent_transform_step->updateInputStream(current_node->step->getOutputStream());
+            DataStreams streams;
+            streams.reserve(current_node->children.size());
+            for (const auto * child : current_node->children)
+                streams.emplace_back(child->step->getOutputStream());
+
+            current_step.updateInputStreams(std::move(streams));
         }
     };
 
diff --git a/src/Processors/QueryPlan/UnionStep.cpp b/src/Processors/QueryPlan/UnionStep.cpp
index e111890a833..dde12271de1 100644
--- a/src/Processors/QueryPlan/UnionStep.cpp
+++ b/src/Processors/QueryPlan/UnionStep.cpp
@@ -30,18 +30,16 @@ UnionStep::UnionStep(DataStreams input_streams_, size_t max_threads_)
     : header(checkHeaders(input_streams_))
     , max_threads(max_threads_)
 {
-    input_streams = std::move(input_streams_);
+    updateInputStreams(std::move(input_streams_));
+}
 
+void UnionStep::updateOutputStream()
+{
     if (input_streams.size() == 1)
         output_stream = input_streams.front();
     else
         output_stream = DataStream{.header = header};
 
-    updateOutputSortDescription();
-}
-
-void UnionStep::updateOutputSortDescription()
-{
     SortDescription common_sort_description = input_streams.front().sort_description;
     DataStream::SortScope sort_scope = input_streams.front().sort_scope;
     for (const auto & input_stream : input_streams)
diff --git a/src/Processors/QueryPlan/UnionStep.h b/src/Processors/QueryPlan/UnionStep.h
index 6278de07673..4ab08785b01 100644
--- a/src/Processors/QueryPlan/UnionStep.h
+++ b/src/Processors/QueryPlan/UnionStep.h
@@ -19,9 +19,11 @@ public:
 
     size_t getMaxThreads() const { return max_threads; }
 
-    void updateOutputSortDescription();
+    bool canUpdateInputStream() const override { return true; }
 
 private:
+    void updateOutputStream() override;
+
     Block header;
     size_t max_threads;
 };
diff --git a/tests/queries/0_stateless/02703_keeper_map_concurrent_create_drop.sh b/tests/queries/0_stateless/02703_keeper_map_concurrent_create_drop.sh
index 3964427895c..17d1fa92377 100755
--- a/tests/queries/0_stateless/02703_keeper_map_concurrent_create_drop.sh
+++ b/tests/queries/0_stateless/02703_keeper_map_concurrent_create_drop.sh
@@ -15,7 +15,8 @@ function create_drop_loop()
     done
 
     i=0
-    while true;
+    local TIMELIMIT=$((SECONDS+$2))
+    while [ $SECONDS -lt "$TIMELIMIT" ];
     do
         $CLICKHOUSE_CLIENT --query="CREATE TABLE IF NOT EXISTS $table_name (key UInt64, value UInt64) ENGINE = KeeperMap('/02703_keeper_map/$CLICKHOUSE_DATABASE') PRIMARY KEY(key)"
         $CLICKHOUSE_CLIENT --query="INSERT INTO $table_name VALUES ($1, $i)"
@@ -40,7 +41,7 @@ TIMEOUT=30
 
 for i in `seq $THREADS`
 do
-    timeout $TIMEOUT bash -c "create_drop_loop $i" 2> /dev/null &
+    create_drop_loop $i $TIMEOUT 2> /dev/null &
 done
 
 wait
diff --git a/tests/queries/0_stateless/02876_sort_union_of_sorted.reference b/tests/queries/0_stateless/02876_sort_union_of_sorted.reference
new file mode 100644
index 00000000000..f3af221a036
--- /dev/null
+++ b/tests/queries/0_stateless/02876_sort_union_of_sorted.reference
@@ -0,0 +1,63 @@
+1..20:
+1
+2
+3
+4
+5
+6
+7
+8
+9
+10
+11
+12
+13
+14
+15
+16
+17
+18
+19
+20
+20..1:
+20
+19
+18
+17
+16
+15
+14
+13
+12
+11
+10
+9
+8
+7
+6
+5
+4
+3
+2
+1
+20..1:
+20
+19
+18
+17
+16
+15
+14
+13
+12
+11
+10
+9
+8
+7
+6
+5
+4
+3
+2
+1
diff --git a/tests/queries/0_stateless/02876_sort_union_of_sorted.sql b/tests/queries/0_stateless/02876_sort_union_of_sorted.sql
new file mode 100644
index 00000000000..23d3772bc82
--- /dev/null
+++ b/tests/queries/0_stateless/02876_sort_union_of_sorted.sql
@@ -0,0 +1,20 @@
+DROP TABLE IF EXISTS table1;
+DROP TABLE IF EXISTS table2;
+
+CREATE TABLE table1 (number UInt64) ENGINE=MergeTree ORDER BY tuple();
+CREATE TABLE table2 (number UInt64) ENGINE=MergeTree ORDER BY tuple();
+
+INSERT INTO table1 SELECT number FROM numbers_mt(1, 10);
+INSERT INTO table2 SELECT number FROM numbers_mt(11, 10);
+
+SELECT '1..20:';
+SELECT * FROM ((SELECT * FROM table1 ORDER BY number) UNION ALL (SELECT * FROM table2 ORDER BY number)) ORDER BY number;
+
+SELECT '20..1:';
+SELECT * FROM ((SELECT * FROM table1 ORDER BY number) UNION ALL (SELECT * FROM table2 ORDER BY number)) ORDER BY number DESC;
+
+SELECT '20..1:';
+SELECT * FROM ((SELECT * FROM table1 ORDER BY number DESC) UNION ALL (SELECT * FROM table2 ORDER BY number DESC)) ORDER BY number DESC;
+
+DROP TABLE table1;
+DROP TABLE table2;