Better

contrib/capnproto

@@ -1 +1 @@
-Subproject commit dc8b50b999777bcb23c89bb5907c785c3f654441
+Subproject commit 976209a6d18074804f60d18ef99b6a809d27dadf

src/Storages/addColumnsStructureToQueryWithClusterEngine.cpp

@@ -0,0 +1,52 @@
+#include <Storages/addColumnsStructureToQueryWithClusterEngine.h>
+#include <Parsers/ASTExpressionList.h>
+#include <Parsers/ASTSelectQuery.h>
+#include <Parsers/ASTTablesInSelectQuery.h>
+#include <Parsers/ASTFunction.h>
+#include <Parsers/ASTLiteral.h>
+#include <Parsers/queryToString.h>
+
+namespace DB
+{
+
+namespace ErrorCodes
+{
+    extern const int LOGICAL_ERROR;
+}
+
+ASTExpressionList * extractTableFunctionArgumentsFromSelectQuery(ASTPtr & query)
+{
+    auto * select_query = query->as<ASTSelectQuery>();
+    if (!select_query || !select_query->tables())
+        return nullptr;
+
+    auto * tables = select_query->tables()->as<ASTTablesInSelectQuery>();
+    auto * table_expression = tables->children[0]->as<ASTTablesInSelectQueryElement>()->table_expression->as<ASTTableExpression>();
+    if (!table_expression->table_function)
+        return nullptr;
+
+    auto * table_function = table_expression->table_function->as<ASTFunction>();
+    return table_function->arguments->as<ASTExpressionList>();
+}
+
+void addColumnsStructureToQueryWithClusterEngine(ASTPtr & query, const String & structure, size_t max_arguments, const String & function_name)
+{
+    ASTExpressionList * expression_list = extractTableFunctionArgumentsFromSelectQuery(query);
+    if (!expression_list)
+        throw Exception(ErrorCodes::LOGICAL_ERROR, "Expected SELECT query from table function {}, got '{}'", function_name, queryToString(query));
+    auto structure_literal = std::make_shared<ASTLiteral>(structure);
+
+    if (expression_list->children.size() < 2 || expression_list->children.size() > max_arguments)
+        throw Exception(ErrorCodes::LOGICAL_ERROR, "Expected 2 to {} arguments in {} table functions, got {}",
+                        function_name, max_arguments, expression_list->children.size());
+
+    if (expression_list->children.size() == 2 || expression_list->children.size() == max_arguments - 1)
+    {
+        auto format_literal = std::make_shared<ASTLiteral>("auto");
+        expression_list->children.push_back(format_literal);
+    }
+
+    expression_list->children.push_back(structure_literal);
+}
+
+}

src/Storages/addColumnsStructureToQueryWithClusterEngine.h

@@ -0,0 +1,14 @@
+#pragma once
+
+#include <Parsers/IAST.h>
+#include <Parsers/ASTExpressionList.h>
+
+namespace DB
+{
+
+ASTExpressionList * extractTableFunctionArgumentsFromSelectQuery(ASTPtr & query);
+
+/// Add structure argument for queries with s3Cluster/hdfsCluster table function.
+void addColumnsStructureToQueryWithClusterEngine(ASTPtr & query, const String & structure, size_t max_arguments, const String & function_name);
+
+}