has one progress

include/matador/sql/internal/object_resolver_producer.hpp

@@ -27,5 +27,24 @@ protected:
 private:
   std::type_index type_;
 };
+
+class joined_object_resolver_producer {
+public:
+  virtual ~joined_object_resolver_producer() = default;
+  virtual utils::result<query_context, utils::error> build_query(const dialect& d) = 0;
+  virtual std::shared_ptr<object::abstract_joined_resolver> produce(statement&& stmt) = 0;
+
+  [[nodiscard]] const std::type_index& root_type() const;
+  [[nodiscard]] const std::type_index& type() const;
+  [[nodiscard]] const std::string& collection_name() const;
+
+protected:
+  explicit joined_object_resolver_producer(const std::type_index &root_type, const std::type_index &type, std::string collection_name);
+
+private:
+  std::type_index root_type_;
+  std::type_index type_;
+  std::string collection_name_;
+};
 }
 #endif //MATADOR_RESOLVER_PRODUCER_HPP