3 files changed, 37 insertions, 10 deletions
diff --git a/src/database/column.hpp b/src/database/column.hpp
index 50c9c14..837aa3f 100644
--- a/src/database/column.hpp
+++ b/src/database/column.hpp
@@ -9,18 +9,30 @@ struct Column
         value{default_value} {}
     Column():
         value{} {}
+    void clear()
+    {
+      this->value = {};
+    }
     using real_type = T;
     T value{};
 };
 
+template <typename T>
+struct UnclearableColumn: public Column<T>
+{
+    using Column<T>::Column;
+    void clear()
+    { }
+};
+
 struct ForeignKey: Column<std::size_t> {
     static constexpr auto name = "fk_";
 };
 
-struct Id: Column<std::size_t> {
+struct Id: UnclearableColumn<std::size_t> {
     static constexpr std::size_t unset_value = static_cast<std::size_t>(-1);
     static constexpr auto name = "id_";
     static constexpr auto options = "PRIMARY KEY";
 
-    Id(): Column<std::size_t>(unset_value) {}
+    Id(): UnclearableColumn<std::size_t>(unset_value) {}
 };
diff --git a/src/database/database.hpp b/src/database/database.hpp
index d986ecc..30ffcb4 100644
--- a/src/database/database.hpp
+++ b/src/database/database.hpp
@@ -27,15 +27,15 @@ class Database
 
   struct Uuid: Column<std::string> { static constexpr auto name = "uuid_"; };
 
-  struct Owner: Column<std::string> { static constexpr auto name = "owner_"; };
+  struct Owner: UnclearableColumn<std::string> { static constexpr auto name = "owner_"; };
 
-  struct IrcChanName: Column<std::string> { static constexpr auto name = "ircchanname_"; };
+  struct IrcChanName: UnclearableColumn<std::string> { static constexpr auto name = "ircchanname_"; };
 
-  struct Channel: Column<std::string> { static constexpr auto name = "channel_"; };
+  struct Channel: UnclearableColumn<std::string> { static constexpr auto name = "channel_"; };
 
-  struct IrcServerName: Column<std::string> { static constexpr auto name = "ircservername_"; };
+  struct IrcServerName: UnclearableColumn<std::string> { static constexpr auto name = "ircservername_"; };
 
-  struct Server: Column<std::string> { static constexpr auto name = "server_"; };
+  struct Server: UnclearableColumn<std::string> { static constexpr auto name = "server_"; };
 
   struct Date: Column<time_point::rep> { static constexpr auto name = "date_"; };
 
diff --git a/src/database/row.hpp b/src/database/row.hpp
index 27caf43..1253f93 100644
--- a/src/database/row.hpp
+++ b/src/database/row.hpp
@@ -1,7 +1,5 @@
 #pragma once
 
-#include <utils/is_one_of.hpp>
-
 #include <type_traits>
 
 template <typename... T>
@@ -25,7 +23,24 @@ struct Row
     return col.value;
   }
 
-public:
+  void clear()
+  {
+    this->clear_col<0>();
+  }
+
   std::tuple<T...> columns;
   std::string table_name;
+
+private:
+  template <std::size_t N>
+  typename std::enable_if<N < sizeof...(T), void>::type
+  clear_col()
+  {
+    std::get<N>(this->columns).clear();
+    this->clear_col<N+1>();
+  }
+  template <std::size_t N>
+  typename std::enable_if<N == sizeof...(T), void>::type
+  clear_col()
+  { }
 };