ecstasy::query::Select< SelectedQueryables > Struct Template Reference

Advanced Query. More...

#include <Select.hpp>

Classes
struct	FilterQueryables
struct	SorteredTie

Public Types
using	SelectedTuple = std::tuple< SelectedQueryables &... >
	Resulting selected Queryable tuple.

Static Public Member Functions
template<typename Conditions = util::meta::Traits<>, Queryable FirstWhere, Queryable... Wheres>
static QueryImplementation< util::meta::Traits< SelectedQueryables... >, Conditions >	where (FirstWhere &firstWhere, Wheres &...wheres)
	Execute a AND query with all the given Queryables but returns only the one in SelectedQueryables.

Static Private Member Functions
template<Queryable Q>
static constexpr bool	isQueryableSelected () noexcept
template<Queryable... Qs>
static constexpr SelectedTuple	tieQueryables (Qs &...queryables) noexcept
template<Queryable... Queryables>
static constexpr SelectedTuple	filterQueryables (Queryables &...queryables) noexcept
	Isolate the given queryables to keep only the SelectedQueryables ones.

Detailed Description

template<Queryable... SelectedQueryables>
struct ecstasy::query::Select< SelectedQueryables >

Advanced Query.

It allows to select which data must be kept from a query request.

Note

Cannot do AutoLock at this scope because of variable lifetimes (see where method). For thread safety, queryables lock must be done before calling the where method.

Template Parameters

SelectedQueryables

Queryables to keep in the resulting query.

Author

Andréas Leroux (andre.nosp@m.as.l.nosp@m.eroux.nosp@m.@epi.nosp@m.tech..nosp@m.eu)

Since

1.0.0 (2022-10-22)

Definition at line 40 of file Select.hpp.

Member Typedef Documentation

SelectedTuple

template<Queryable... SelectedQueryables>

using ecstasy::query::Select< SelectedQueryables >::SelectedTuple = std::tuple<SelectedQueryables &...>

Resulting selected Queryable tuple.

Definition at line 43 of file Select.hpp.

Member Function Documentation

filterQueryables()

template<Queryable... SelectedQueryables>

template<Queryable... Queryables>

static constexpr SelectedTuple ecstasy::query::Select< SelectedQueryables >::filterQueryables ( Queryables &...  queryables )

inlinestaticconstexprprivatenoexcept

Isolate the given queryables to keep only the SelectedQueryables ones.

Template Parameters

Queryables

given queryables types.

Parameters

[in]

queryables

given queryables.

Returns

SelectedTuple selected queryables.

Author

Andréas Leroux (andre.nosp@m.as.l.nosp@m.eroux.nosp@m.@epi.nosp@m.tech..nosp@m.eu)

Since

1.0.0 (2022-10-22)

Definition at line 239 of file Select.hpp.

        {
            return FilterQueryables<isQueryableSelected<typename util::meta::Traits<Queryables...>::First>(),
                typename util::meta::Traits<Queryables...>::First>::value(std::forward<Queryables &>(queryables)...);
        }

isQueryableSelected()

template<Queryable... SelectedQueryables>

template<Queryable Q>

static constexpr bool ecstasy::query::Select< SelectedQueryables >::isQueryableSelected ( )

inlinestaticconstexprprivatenoexcept

Definition at line 57 of file Select.hpp.

        {
            return util::meta::contains<Q, SelectedQueryables...>;
        }

tieQueryables()

template<Queryable... SelectedQueryables>

template<Queryable... Qs>

static constexpr SelectedTuple ecstasy::query::Select< SelectedQueryables >::tieQueryables ( Qs &...  queryables )

inlinestaticconstexprprivatenoexcept

Definition at line 129 of file Select.hpp.

        {
            static_assert(util::meta::type_set_eq_v<std::tuple<SelectedQueryables...>, std::tuple<Qs...>>,
                "Missing queryables in where clause");
            if constexpr (std::is_same_v<std::tuple<SelectedQueryables...>, std::tuple<Qs...>>)
                return std::tie(std::forward<Qs &>(queryables)...);
            else
                return SorteredTie<>::template sort(std::forward<Qs &>(queryables)...);
        }

where()

template<Queryable... SelectedQueryables>

template<typename Conditions = util::meta::Traits<>, Queryable FirstWhere, Queryable... Wheres>

static QueryImplementation< util::meta::Traits< SelectedQueryables... >, Conditions > ecstasy::query::Select< SelectedQueryables >::where ( FirstWhere &  firstWhere, Wheres &...  wheres  )

inlinestatic

Execute a AND query with all the given Queryables but returns only the one in SelectedQueryables.

Warning

All queryables specified in SelectedQueryables must be passed as parameters.

Template Parameters

Conditions	util::meta::Traits of multiple Condition.
FirstWhere	First Queryable type.
Wheres	Others Queryable types.

Parameters

[in]	firstWhere	first Queryable instance.
[in]	wheres	others Queryable instances.

Returns

QueryImplementation<util::meta::Traits<SelectedQueryables...>, Conditions> Resulting query that can be iterated.

Author

Andréas Leroux (andre.nosp@m.as.l.nosp@m.eroux.nosp@m.@epi.nosp@m.tech..nosp@m.eu)

Since

1.0.0 (2022-10-22)

Adjusts the masks only if required

Definition at line 265 of file Select.hpp.

        {
            if constexpr (is_queryable_with_adjust_v<FirstWhere>
                || std::disjunction_v<is_queryable_with_adjust<Wheres>...>) {
                size_t maxSize = std::max({getQueryableMask(firstWhere).size(), getQueryableMask(wheres).size()...});
 
                adjustMask(firstWhere, maxSize);
                (adjustMask(wheres, maxSize), ...);
            }
 
            util::BitSet mask = (util::BitSet(getQueryableMask(firstWhere)) &= ... &= getQueryableMask(wheres));
 
            return QueryImplementation<util::meta::Traits<SelectedQueryables...>, Conditions>(
                mask, filterQueryables(firstWhere, wheres...));
        }

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The documentation for this struct was generated from the following file:

• src/ecstasy/query/Select.hpp