diff --git a/dbms/src/Interpreters/ClusterProxy/DescribeStreamFactory.cpp b/dbms/src/Interpreters/ClusterProxy/DescribeStreamFactory.cpp
index 81a15720899..2638399f8ff 100644
--- a/dbms/src/Interpreters/ClusterProxy/DescribeStreamFactory.cpp
+++ b/dbms/src/Interpreters/ClusterProxy/DescribeStreamFactory.cpp
@@ -29,7 +29,7 @@ namespace ClusterProxy
 void DescribeStreamFactory::createForShard(
         const Cluster::ShardInfo & shard_info,
         const String & query, const ASTPtr & query_ast,
-        const ThrottlerPtr & throttler, Context & context,
+        const Context & context, const ThrottlerPtr & throttler,
         BlockInputStreams & res)
 {
     for (const Cluster::Address & local_address : shard_info.local_addresses)
diff --git a/dbms/src/Interpreters/ClusterProxy/DescribeStreamFactory.h b/dbms/src/Interpreters/ClusterProxy/DescribeStreamFactory.h
index 7e3cd0db138..05befc59305 100644
--- a/dbms/src/Interpreters/ClusterProxy/DescribeStreamFactory.h
+++ b/dbms/src/Interpreters/ClusterProxy/DescribeStreamFactory.h
@@ -14,7 +14,7 @@ public:
     void createForShard(
         const Cluster::ShardInfo & shard_info,
         const String & query, const ASTPtr & query_ast,
-        const ThrottlerPtr & throttler, Context & context,
+        const Context & context, const ThrottlerPtr & throttler,
         BlockInputStreams & res) override;
 };
 
diff --git a/dbms/src/Interpreters/ClusterProxy/IStreamFactory.h b/dbms/src/Interpreters/ClusterProxy/IStreamFactory.h
index 15d840028ae..beceaaecce2 100644
--- a/dbms/src/Interpreters/ClusterProxy/IStreamFactory.h
+++ b/dbms/src/Interpreters/ClusterProxy/IStreamFactory.h
@@ -26,7 +26,7 @@ public:
     virtual void createForShard(
             const Cluster::ShardInfo & shard_info,
             const String & query, const ASTPtr & query_ast,
-            const ThrottlerPtr & throttler, Context & context,
+            const Context & context, const ThrottlerPtr & throttler,
             BlockInputStreams & res) = 0;
 };
 
diff --git a/dbms/src/Interpreters/ClusterProxy/SelectStreamFactory.cpp b/dbms/src/Interpreters/ClusterProxy/SelectStreamFactory.cpp
index 6ad7e407b85..24060eedcd7 100644
--- a/dbms/src/Interpreters/ClusterProxy/SelectStreamFactory.cpp
+++ b/dbms/src/Interpreters/ClusterProxy/SelectStreamFactory.cpp
@@ -59,7 +59,7 @@ BlockInputStreamPtr createLocalStream(const ASTPtr & query_ast, const Context &
 void SelectStreamFactory::createForShard(
     const Cluster::ShardInfo & shard_info,
     const String & query, const ASTPtr & query_ast,
-    const ThrottlerPtr & throttler, Context & context,
+    const Context & context, const ThrottlerPtr & throttler,
     BlockInputStreams & res)
 {
     auto emplace_local_stream = [&]()
diff --git a/dbms/src/Interpreters/ClusterProxy/SelectStreamFactory.h b/dbms/src/Interpreters/ClusterProxy/SelectStreamFactory.h
index 2d3666f2874..5325e5d463c 100644
--- a/dbms/src/Interpreters/ClusterProxy/SelectStreamFactory.h
+++ b/dbms/src/Interpreters/ClusterProxy/SelectStreamFactory.h
@@ -22,7 +22,7 @@ public:
     void createForShard(
         const Cluster::ShardInfo & shard_info,
         const String & query, const ASTPtr & query_ast,
-        const ThrottlerPtr & throttler, Context & context,
+        const Context & context, const ThrottlerPtr & throttler,
         BlockInputStreams & res) override;
 
 private:
diff --git a/dbms/src/Interpreters/ClusterProxy/executeQuery.cpp b/dbms/src/Interpreters/ClusterProxy/executeQuery.cpp
index aeb02bc9262..27b7d8338af 100644
--- a/dbms/src/Interpreters/ClusterProxy/executeQuery.cpp
+++ b/dbms/src/Interpreters/ClusterProxy/executeQuery.cpp
@@ -57,7 +57,7 @@ BlockInputStreams executeQuery(
         throttler = user_level_throttler;
 
     for (const auto & shard_info : cluster->getShardsInfo())
-        stream_factory.createForShard(shard_info, query, query_ast, throttler, new_context, res);
+        stream_factory.createForShard(shard_info, query, query_ast, new_context, throttler, res);
 
     return res;
 }
diff --git a/dbms/src/Interpreters/InterpreterDropQuery.cpp b/dbms/src/Interpreters/InterpreterDropQuery.cpp
index f13b9693e92..cdb107a13ad 100644
--- a/dbms/src/Interpreters/InterpreterDropQuery.cpp
+++ b/dbms/src/Interpreters/InterpreterDropQuery.cpp
@@ -20,6 +20,7 @@ namespace ErrorCodes
     extern const int UNKNOWN_DATABASE;
     extern const int READONLY;
     extern const int LOGICAL_ERROR;
+    extern const int SYNTAX_ERROR;
     extern const int UNKNOWN_TABLE;
 }
 
diff --git a/dbms/src/Parsers/ASTDropQuery.cpp b/dbms/src/Parsers/ASTDropQuery.cpp
new file mode 100644
index 00000000000..dff25e7023e
--- /dev/null
+++ b/dbms/src/Parsers/ASTDropQuery.cpp
@@ -0,0 +1,72 @@
+#include <Parsers/ASTDropQuery.h>
+
+
+namespace DB
+{
+
+namespace ErrorCodes
+{
+    extern const int SYNTAX_ERROR;
+}
+
+
+String ASTDropQuery::getID() const
+{
+    if (kind == ASTDropQuery::Kind::Drop)
+        return "DropQuery_" + database + "_" + table;
+    else if (kind == ASTDropQuery::Kind::Detach)
+        return "DetachQuery_" + database + "_" + table;
+    else if (kind == ASTDropQuery::Kind::Truncate)
+        return "TruncateQuery_" + database + "_" + table;
+    else
+        throw Exception("Not supported kind of drop query.", ErrorCodes::SYNTAX_ERROR);
+}
+
+ASTPtr ASTDropQuery::clone() const
+{
+    auto res = std::make_shared<ASTDropQuery>(*this);
+    cloneOutputOptions(*res);
+    return res;
+}
+
+ASTPtr ASTDropQuery::getRewrittenASTWithoutOnCluster(const std::string & new_database) const
+{
+    auto query_ptr = clone();
+    auto & query = static_cast<ASTDropQuery &>(*query_ptr);
+
+    query.cluster.clear();
+    if (query.database.empty())
+        query.database = new_database;
+
+    return query_ptr;
+}
+
+void ASTDropQuery::formatQueryImpl(const FormatSettings & settings, FormatState &, FormatStateStacked) const
+{
+    settings.ostr << (settings.hilite ? hilite_keyword : "");
+    if (kind == ASTDropQuery::Kind::Drop)
+        settings.ostr << "DROP ";
+    else if (kind == ASTDropQuery::Kind::Detach)
+        settings.ostr << "DETACH ";
+    else if (kind == ASTDropQuery::Kind::Truncate)
+        settings.ostr << "TRUNCATE ";
+    else
+        throw Exception("Not supported kind of drop query.", ErrorCodes::SYNTAX_ERROR);
+
+    settings.ostr << ((table.empty() && !database.empty()) ? "DATABASE " : "TABLE ");
+
+    if (if_exists)
+        settings.ostr << "IF EXISTS ";
+
+    settings.ostr << (settings.hilite ? hilite_none : "");
+
+    if (table.empty() && !database.empty())
+        settings.ostr << backQuoteIfNeed(database);
+    else
+        settings.ostr << (!database.empty() ? backQuoteIfNeed(database) + "." : "") << backQuoteIfNeed(table);
+
+    formatOnCluster(settings);
+}
+
+}
+
diff --git a/dbms/src/Parsers/ASTDropQuery.h b/dbms/src/Parsers/ASTDropQuery.h
index 67da3346964..64d30b9453f 100644
--- a/dbms/src/Parsers/ASTDropQuery.h
+++ b/dbms/src/Parsers/ASTDropQuery.h
@@ -1,17 +1,12 @@
 #pragma once
 
-#include <Parsers/IAST.h>
 #include <Parsers/ASTQueryWithOutput.h>
 #include <Parsers/ASTQueryWithOnCluster.h>
 
+
 namespace DB
 {
 
-namespace ErrorCodes
-{
-    extern const int SYNTAX_ERROR;
-}
-
 /** DROP query
   */
 class ASTDropQuery : public ASTQueryWithOutput, public ASTQueryWithOnCluster
@@ -31,72 +26,13 @@ public:
     String table;
 
     /** Get the text that identifies this element. */
-    String getID() const override
-    {
-        if (kind == ASTDropQuery::Kind::Drop)
-            return "DropQuery_" + database + "_" + table;
-        else if (kind == ASTDropQuery::Kind::Detach)
-            return "DetachQuery_" + database + "_" + table;
-        else if (kind == ASTDropQuery::Kind::Truncate)
-            return "TruncateQuery_" + database + "_" + table;
-        else
-            throw Exception("Not supported kind of drop query.", ErrorCodes::SYNTAX_ERROR);
-    }
+    String getID() const override;
+    ASTPtr clone() const override;
 
-    ASTPtr clone() const override
-    {
-        auto res = std::make_shared<ASTDropQuery>(*this);
-        cloneOutputOptions(*res);
-        return res;
-    }
-
-    ASTPtr getRewrittenASTWithoutOnCluster(const std::string & new_database) const override
-    {
-        auto query_ptr = clone();
-        auto & query = static_cast<ASTDropQuery &>(*query_ptr);
-
-        query.cluster.clear();
-        if (query.database.empty())
-            query.database = new_database;
-
-        return query_ptr;
-    }
+    ASTPtr getRewrittenASTWithoutOnCluster(const std::string & new_database) const override;
 
 protected:
-    void formatQueryImpl(const FormatSettings & settings, FormatState &, FormatStateStacked) const override
-    {
-        if (table.empty() && !database.empty())
-        {
-            settings.ostr << (settings.hilite ? hilite_keyword : "");
-            if (kind == ASTDropQuery::Kind::Drop)
-                settings.ostr << "DROP DATABASE ";
-            else if (kind == ASTDropQuery::Kind::Detach)
-                settings.ostr << "DETACH DATABASE ";
-            else if (kind == ASTDropQuery::Kind::Truncate)
-                settings.ostr << "TRUNCATE DATABASE ";
-            else
-                throw Exception("Not supported kind of drop query.", ErrorCodes::SYNTAX_ERROR);
-
-            settings.ostr << (if_exists ? "IF EXISTS " : "") << (settings.hilite ? hilite_none : "") << backQuoteIfNeed(database);
-            formatOnCluster(settings);
-        }
-        else
-        {
-            settings.ostr << (settings.hilite ? hilite_keyword : "");
-            if (kind == ASTDropQuery::Kind::Drop)
-                settings.ostr << "DROP TABLE ";
-            else if (kind == ASTDropQuery::Kind::Detach)
-                settings.ostr << "DETACH TABLE ";
-            else if (kind == ASTDropQuery::Kind::Truncate)
-                settings.ostr << "TRUNCATE TABLE ";
-            else
-                throw Exception("Not supported kind of drop query.", ErrorCodes::SYNTAX_ERROR);
-
-            settings.ostr << (if_exists ? "IF EXISTS " : "") << (settings.hilite ? hilite_none : "")
-                          << (!database.empty() ? backQuoteIfNeed(database) + "." : "") << backQuoteIfNeed(table);
-            formatOnCluster(settings);
-        }
-    }
+    void formatQueryImpl(const FormatSettings & settings, FormatState &, FormatStateStacked) const override;
 };
 
 }