tables::table::group_by

template <typename... Ts,is_primitive_type... Ps>
template<typename... Gs>
requires ( ( in<Gs,std::tuple<Ts...>> && ... ) && is_tuple_unique<std::tuple<Gs...>> )
inline
gtable<table<std::pair<Ts,Ps>...>,std::tuple<Gs...>>
table<std::pair<Ts,Ps>...>::group_by() const

template <typename... Ts,is_primitive_type... Ps>
template<tuple_ext::is_tuple Gs>
requires ( all_in<Gs,std::tuple<Ts...>> && is_tuple_unique<Gs> )
inline
gtable<table<std::pair<Ts,Ps>...>,Gs>
table<std::pair<Ts,Ps>...>::group_by() const