Represents a value that can be any of the supported SQL data types. More...

#include <SqlVariant.hpp>

Public Types
using	InnerType = std::variant< SqlNullType, SqlGuid, bool, int8_t, short, unsigned short, int, unsigned int, long long, unsigned long long, float, double, std::string, std::string_view, std::u16string, std::u16string_view, SqlText, SqlBinary, SqlDynamicNumeric, SqlDate, SqlTime, SqlDateTime >
	The inner type of the variant.

Public Member Functions
	SqlVariant ()=default
	Default construct a new SqlVariant.

	SqlVariant (SqlVariant const &)=default
	Copy construct a new SqlVariant from another.

	SqlVariant (SqlVariant &&) noexcept=default
	Move construct a new SqlVariant from another.

SqlVariant &	operator= (SqlVariant const &)=default
	Copy assign a new SqlVariant from another.

SqlVariant &	operator= (SqlVariant &&) noexcept=default
	Move assign a new SqlVariant from another.

	~SqlVariant ()=default
	Destructor for SqlVariant.

LIGHTWEIGHT_FORCE_INLINE	SqlVariant (InnerType const &other)
	Copy constructor of a SqlVariant from one of the supported types.

LIGHTWEIGHT_FORCE_INLINE	SqlVariant (InnerType &&other) noexcept
	Move constructor of a SqlVariant from one of the supported types.

template<std::size_t N, typename T = char, SqlFixedStringMode Mode>
constexpr LIGHTWEIGHT_FORCE_INLINE	SqlVariant (SqlFixedString< N, T, Mode > const &other)
	Construct a new SqlVariant from a SqlFixedString.

template<std::size_t N>
LIGHTWEIGHT_FORCE_INLINE	SqlVariant (SqlDynamicBinary< N > const &other)
	Construct a new SqlVariant from a SqlDynamicBinary, holding a copy of its bytes as SqlBinary. This is what lets a binary column be compared in a query builder's WHERE clause, which binds its values as SqlVariant.

template<std::size_t TextSize>
constexpr LIGHTWEIGHT_FORCE_INLINE	SqlVariant (char const (&text)[TextSize])
	Copy constructor of a SqlVariant from a char array.

template<std::size_t TextSize>
constexpr LIGHTWEIGHT_FORCE_INLINE	SqlVariant (char16_t const (&text)[TextSize])
	Copy constructor of a SqlVariant from a char16_t array.

template<typename T >
LIGHTWEIGHT_FORCE_INLINE	SqlVariant (std::optional< T > const &other)
	Copy constructor of a SqlVariant from an optional of one of the supported types.

LIGHTWEIGHT_FORCE_INLINE SqlVariant &	operator= (InnerType const &other)
	Assignment operator of a SqlVariant from one of the supported types.

LIGHTWEIGHT_FORCE_INLINE SqlVariant &	operator= (InnerType &&other) noexcept
	Assignment operator of a SqlVariant from one of the supported types.

template<detail::HasSqlViewHelper StringViewLike>
LIGHTWEIGHT_FORCE_INLINE	SqlVariant (StringViewLike const *newValue)
	Construct from an string-like object that implements an SqlViewHelper<>.

template<detail::HasSqlViewHelper StringViewLike>
LIGHTWEIGHT_FORCE_INLINE SqlVariant &	operator= (StringViewLike const *newValue) noexcept
	Assign from an string-like object that implements an SqlViewHelper<>.

LIGHTWEIGHT_FORCE_INLINE bool	IsNull () const noexcept
	Check if the value is NULL.

template<typename T >
LIGHTWEIGHT_FORCE_INLINE bool	Is () const noexcept
	Check if the value is of the specified type.

template<typename T >
LIGHTWEIGHT_FORCE_INLINE decltype(auto)	Get ()
	Retrieve the value as the specified type.

template<typename T >
LIGHTWEIGHT_FORCE_INLINE T	ValueOr (T &&defaultValue) const noexcept
	Retrieve the value as the specified type, or return the default value if the value is NULL.

LIGHTWEIGHT_FORCE_INLINE std::optional< bool >	TryGetBool () const noexcept
	Retrieve the bool from the variant or std::nullopt.

LIGHTWEIGHT_FORCE_INLINE std::optional< int8_t >	TryGetInt8 () const noexcept
	Retrieve the int8_t from the variant or std::nullopt.

LIGHTWEIGHT_FORCE_INLINE std::optional< short >	TryGetShort () const noexcept
	Retrieve the unsigned short from the variant or std::nullopt.

LIGHTWEIGHT_FORCE_INLINE std::optional< unsigned short >	TryGetUShort () const noexcept
	Retrieve the unsigned short from the variant or std::nullopt.

LIGHTWEIGHT_FORCE_INLINE std::optional< int >	TryGetInt () const noexcept
	Retrieve the int from the variant or std::nullopt.

LIGHTWEIGHT_FORCE_INLINE std::optional< unsigned int >	TryGetUInt () const noexcept
	Retrieve the unsigned int from the variant or std::nullopt.

LIGHTWEIGHT_FORCE_INLINE std::optional< long long >	TryGetLongLong () const noexcept
	Retrieve the long long from the variant or std::nullopt.

LIGHTWEIGHT_FORCE_INLINE std::optional< unsigned long long >	TryGetULongLong () const noexcept
	Retrieve the unsigned long long from the variant or std::nullopt.

std::optional< std::string_view >	TryGetStringView () const noexcept
	Retrieves a string view from the variant, or `std::nullopt` if the variant is NULL or holds a non-string alternative. The function is `noexcept`, so it must not propagate `bad_variant_access`.

std::optional< std::u16string_view >	TryGetUtf16StringView () const noexcept
	Retrieves a UTF-16 string view from the variant, or `std::nullopt` if the variant is NULL or holds a non-string alternative. The function is `noexcept`, so it must not propagate `bad_variant_access`.

LIGHTWEIGHT_FORCE_INLINE std::optional< SqlDate >	TryGetDate () const
	function to get SqlDate from SqlVariant or std::nullopt

bool	operator== (SqlVariant const &other) const noexcept
	Equality comparison operator.

bool	operator!= (SqlVariant const &other) const noexcept
	Inequality comparison operator.

LIGHTWEIGHT_FORCE_INLINE std::optional< SqlTime >	TryGetTime () const
	function to get SqlTime from SqlVariant or std::nullopt

LIGHTWEIGHT_FORCE_INLINE std::optional< SqlDateTime >	TryGetDateTime () const
	function to get SqlDateTime from SqlVariant or std::nullopt

LIGHTWEIGHT_FORCE_INLINE std::optional< SqlGuid >	TryGetGuid () const
	Retrieve the GUID from the variant or std::nullopt if the value is NULL.

LIGHTWEIGHT_FORCE_INLINE std::optional< SqlDynamicNumeric >	TryGetNumeric () const
	Retrieve the exact fixed-point decimal from the variant, or std::nullopt if NULL.

LIGHTWEIGHT_FORCE_INLINE std::optional< SqlBinary >	TryGetBinary () const
	Retrieve the binary payload from the variant, or std::nullopt if the value is NULL.

LIGHTWEIGHT_API std::string	ToString () const
	Create string representation of the variant. Can be used for debug purposes.

Public Attributes
InnerType	value
	The variant value.

Detailed Description

Represents a value that can be any of the supported SQL data types.

Use this class with care. Always prefer native types when possible, in order to avoid any unnecessary overhead.

Definition at line 47 of file SqlVariant.hpp.

Member Typedef Documentation

◆ InnerType

using Lightweight::SqlVariant::InnerType = std::variant<SqlNullType, SqlGuid, bool, int8_t, short, unsigned short, int, unsigned int, long long, unsigned long long, float, double, std::string, std::string_view, std::u16string, std::u16string_view, SqlText, SqlBinary, SqlDynamicNumeric, SqlDate, SqlTime, SqlDateTime>

The inner type of the variant.

This type is a variant of all the supported SQL data types.

Definition at line 52 of file SqlVariant.hpp.

Constructor & Destructor Documentation

◆ SqlVariant() [1/8]

LIGHTWEIGHT_FORCE_INLINE Lightweight::SqlVariant::SqlVariant ( InnerType const & other )

inline

Copy constructor of a SqlVariant from one of the supported types.

Definition at line 92 of file SqlVariant.hpp.

◆ SqlVariant() [2/8]

LIGHTWEIGHT_FORCE_INLINE Lightweight::SqlVariant::SqlVariant ( InnerType && other )

inlinenoexcept

Move constructor of a SqlVariant from one of the supported types.

Definition at line 98 of file SqlVariant.hpp.

◆ SqlVariant() [3/8]

template<std::size_t N, typename T = char, SqlFixedStringMode Mode>

constexpr LIGHTWEIGHT_FORCE_INLINE Lightweight::SqlVariant::SqlVariant ( SqlFixedString< N, T, Mode > const & other )

inlineconstexpr

Construct a new SqlVariant from a SqlFixedString.

Definition at line 105 of file SqlVariant.hpp.

◆ SqlVariant() [4/8]

template<std::size_t N>

LIGHTWEIGHT_FORCE_INLINE Lightweight::SqlVariant::SqlVariant ( SqlDynamicBinary< N > const & other )

inline

Construct a new SqlVariant from a SqlDynamicBinary, holding a copy of its bytes as SqlBinary. This is what lets a binary column be compared in a query builder's WHERE clause, which binds its values as SqlVariant.

Definition at line 114 of file SqlVariant.hpp.

◆ SqlVariant() [5/8]

template<std::size_t TextSize>

constexpr LIGHTWEIGHT_FORCE_INLINE Lightweight::SqlVariant::SqlVariant ( char const (&) text[TextSize] )

inlineconstexpr

Copy constructor of a SqlVariant from a char array.

Definition at line 121 of file SqlVariant.hpp.

◆ SqlVariant() [6/8]

template<std::size_t TextSize>

constexpr LIGHTWEIGHT_FORCE_INLINE Lightweight::SqlVariant::SqlVariant ( char16_t const (&) text[TextSize] )

inlineconstexpr

Copy constructor of a SqlVariant from a char16_t array.

Definition at line 128 of file SqlVariant.hpp.

◆ SqlVariant() [7/8]

template<typename T >

LIGHTWEIGHT_FORCE_INLINE Lightweight::SqlVariant::SqlVariant ( std::optional< T > const & other )

inline

Copy constructor of a SqlVariant from an optional of one of the supported types.

Definition at line 135 of file SqlVariant.hpp.

◆ SqlVariant() [8/8]

template<detail::HasSqlViewHelper StringViewLike>

LIGHTWEIGHT_FORCE_INLINE Lightweight::SqlVariant::SqlVariant ( StringViewLike const * newValue )

inlineexplicit

Construct from an string-like object that implements an SqlViewHelper<>.

Definition at line 156 of file SqlVariant.hpp.

Member Function Documentation

◆ operator=() [1/3]

LIGHTWEIGHT_FORCE_INLINE SqlVariant & Lightweight::SqlVariant::operator= ( InnerType const & other )

inline

Assignment operator of a SqlVariant from one of the supported types.

Definition at line 141 of file SqlVariant.hpp.

References value.

◆ operator=() [2/3]

LIGHTWEIGHT_FORCE_INLINE SqlVariant & Lightweight::SqlVariant::operator= ( InnerType && other )

inlinenoexcept

Assignment operator of a SqlVariant from one of the supported types.

Definition at line 148 of file SqlVariant.hpp.

References value.

◆ operator=() [3/3]

template<detail::HasSqlViewHelper StringViewLike>

LIGHTWEIGHT_FORCE_INLINE SqlVariant & Lightweight::SqlVariant::operator= ( StringViewLike const * newValue )

inlinenoexcept

Assign from an string-like object that implements an SqlViewHelper<>.

Definition at line 163 of file SqlVariant.hpp.

References value.

◆ IsNull()

LIGHTWEIGHT_FORCE_INLINE bool Lightweight::SqlVariant::IsNull ( ) const

inlinenoexcept

Check if the value is NULL.

Definition at line 170 of file SqlVariant.hpp.

References value.

Referenced by Get(), TryGetBinary(), TryGetDate(), TryGetDateTime(), TryGetGuid(), TryGetNumeric(), TryGetStringView(), TryGetTime(), TryGetUtf16StringView(), and ValueOr().

◆ Is()

template<typename T >

LIGHTWEIGHT_FORCE_INLINE bool Lightweight::SqlVariant::Is ( ) const

inlinenoexcept

Check if the value is of the specified type.

Definition at line 177 of file SqlVariant.hpp.

References value.

◆ Get()

template<typename T >

LIGHTWEIGHT_FORCE_INLINE decltype(auto) Lightweight::SqlVariant::Get ( )

inline

Retrieve the value as the specified type.

Note: A DECIMAL/NUMERIC column fills the SqlDynamicNumeric alternative and a binary column fills SqlBinary. Asking for a floating-point or std::string T converts from those and therefore yields a value rather than a reference. Use TryGetNumeric when the exact decimal matters.

Exceptions

std::bad_variant_access The variant holds neither T nor one of the alternatives converted above. Use the TryGet* accessors to probe instead.

Definition at line 191 of file SqlVariant.hpp.

References IsNull(), and value.

◆ ValueOr()

template<typename T >

LIGHTWEIGHT_FORCE_INLINE T Lightweight::SqlVariant::ValueOr ( T && defaultValue ) const

inlinenoexcept

Retrieve the value as the specified type, or return the default value if the value is NULL.

Note: A DECIMAL/NUMERIC column fills the SqlDynamicNumeric alternative and a binary column fills SqlBinary. Both are converted here when a floating-point or string T is asked for, so callers written against the arithmetic/string alternatives keep working. Reach for TryGetNumeric when the exact decimal matters.

Definition at line 225 of file SqlVariant.hpp.

References IsNull(), and value.

◆ TryGetBool()

LIGHTWEIGHT_FORCE_INLINE std::optional< bool > Lightweight::SqlVariant::TryGetBool ( ) const

inlinenoexcept

Retrieve the bool from the variant or std::nullopt.

Definition at line 257 of file SqlVariant.hpp.

◆ TryGetInt8()

LIGHTWEIGHT_FORCE_INLINE std::optional< int8_t > Lightweight::SqlVariant::TryGetInt8 ( ) const

inlinenoexcept

Retrieve the int8_t from the variant or std::nullopt.

Definition at line 259 of file SqlVariant.hpp.

◆ TryGetShort()

LIGHTWEIGHT_FORCE_INLINE std::optional< short > Lightweight::SqlVariant::TryGetShort ( ) const

inlinenoexcept

Retrieve the unsigned short from the variant or std::nullopt.

Definition at line 261 of file SqlVariant.hpp.

◆ TryGetUShort()

LIGHTWEIGHT_FORCE_INLINE std::optional< unsigned short > Lightweight::SqlVariant::TryGetUShort ( ) const

inlinenoexcept

Retrieve the unsigned short from the variant or std::nullopt.

Definition at line 263 of file SqlVariant.hpp.

◆ TryGetInt()

LIGHTWEIGHT_FORCE_INLINE std::optional< int > Lightweight::SqlVariant::TryGetInt ( ) const

inlinenoexcept

Retrieve the int from the variant or std::nullopt.

Definition at line 265 of file SqlVariant.hpp.

◆ TryGetUInt()

LIGHTWEIGHT_FORCE_INLINE std::optional< unsigned int > Lightweight::SqlVariant::TryGetUInt ( ) const

inlinenoexcept

Retrieve the unsigned int from the variant or std::nullopt.

Definition at line 267 of file SqlVariant.hpp.

◆ TryGetLongLong()

LIGHTWEIGHT_FORCE_INLINE std::optional< long long > Lightweight::SqlVariant::TryGetLongLong ( ) const

inlinenoexcept

Retrieve the long long from the variant or std::nullopt.

Definition at line 269 of file SqlVariant.hpp.

◆ TryGetULongLong()

LIGHTWEIGHT_FORCE_INLINE std::optional< unsigned long long > Lightweight::SqlVariant::TryGetULongLong ( ) const

inlinenoexcept

Retrieve the unsigned long long from the variant or std::nullopt.

Definition at line 271 of file SqlVariant.hpp.

◆ TryGetStringView()

std::optional< std::string_view > Lightweight::SqlVariant::TryGetStringView ( ) const

inlinenoexcept

Retrieves a string view from the variant, or std::nullopt if the variant is NULL or holds a non-string alternative. The function is noexcept, so it must not propagate bad_variant_access.

Definition at line 304 of file SqlVariant.hpp.

References IsNull(), and value.

◆ TryGetUtf16StringView()

std::optional< std::u16string_view > Lightweight::SqlVariant::TryGetUtf16StringView ( ) const

inlinenoexcept

Retrieves a UTF-16 string view from the variant, or std::nullopt if the variant is NULL or holds a non-string alternative. The function is noexcept, so it must not propagate bad_variant_access.

Definition at line 326 of file SqlVariant.hpp.

References IsNull(), and value.

◆ TryGetDate()

LIGHTWEIGHT_FORCE_INLINE std::optional< SqlDate > Lightweight::SqlVariant::TryGetDate ( ) const

inline

function to get SqlDate from SqlVariant or std::nullopt

Definition at line 342 of file SqlVariant.hpp.

References IsNull(), and value.

◆ operator==()

bool Lightweight::SqlVariant::operator== ( SqlVariant const & other ) const

inlinenoexcept

Equality comparison operator.

Definition at line 361 of file SqlVariant.hpp.

References ToString().

◆ operator!=()

bool Lightweight::SqlVariant::operator!= ( SqlVariant const & other ) const

inlinenoexcept

Inequality comparison operator.

Definition at line 367 of file SqlVariant.hpp.

◆ TryGetTime()

LIGHTWEIGHT_FORCE_INLINE std::optional< SqlTime > Lightweight::SqlVariant::TryGetTime ( ) const

inline

function to get SqlTime from SqlVariant or std::nullopt

Definition at line 373 of file SqlVariant.hpp.

References IsNull(), and value.

◆ TryGetDateTime()

LIGHTWEIGHT_FORCE_INLINE std::optional< SqlDateTime > Lightweight::SqlVariant::TryGetDateTime ( ) const

inline

function to get SqlDateTime from SqlVariant or std::nullopt

Definition at line 393 of file SqlVariant.hpp.

References IsNull(), and value.

◆ TryGetGuid()

LIGHTWEIGHT_FORCE_INLINE std::optional< SqlGuid > Lightweight::SqlVariant::TryGetGuid ( ) const

inline

Retrieve the GUID from the variant or std::nullopt if the value is NULL.

Definition at line 405 of file SqlVariant.hpp.

References IsNull(), and value.

◆ TryGetNumeric()

LIGHTWEIGHT_FORCE_INLINE std::optional< SqlDynamicNumeric > Lightweight::SqlVariant::TryGetNumeric ( ) const

inline

Retrieve the exact fixed-point decimal from the variant, or std::nullopt if NULL.

DECIMAL and NUMERIC columns land on this alternative, keeping every digit the column declares. Use SqlDynamicNumeric::ToDouble only where an approximation is acceptable.

Exceptions

std::bad_variant_access The value is neither NULL nor a fixed-point decimal.

Definition at line 422 of file SqlVariant.hpp.

References IsNull(), and value.

◆ TryGetBinary()

LIGHTWEIGHT_FORCE_INLINE std::optional< SqlBinary > Lightweight::SqlVariant::TryGetBinary ( ) const

inline

Retrieve the binary payload from the variant, or std::nullopt if the value is NULL.

BINARY, VARBINARY and LONGVARBINARY columns land on this alternative, which keeps the bytes distinguishable from text so they bind back as SQL_C_BINARY.

Exceptions

std::bad_variant_access The value is neither NULL nor binary.

Definition at line 439 of file SqlVariant.hpp.

References IsNull(), and value.

Member Data Documentation

◆ value

InnerType Lightweight::SqlVariant::value

The variant value.

Definition at line 76 of file SqlVariant.hpp.

Referenced by Get(), Is(), IsNull(), operator=(), operator=(), operator=(), TryGetBinary(), TryGetDate(), TryGetDateTime(), TryGetGuid(), TryGetNumeric(), TryGetStringView(), TryGetTime(), TryGetUtf16StringView(), and ValueOr().

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

Lightweight/DataBinder/SqlVariant.hpp

Public Types

Public Member Functions

Public Attributes

Detailed Description

Member Typedef Documentation

◆ InnerType

Constructor & Destructor Documentation

◆ SqlVariant() [1/8]

◆ SqlVariant() [2/8]

◆ SqlVariant() [3/8]

◆ SqlVariant() [4/8]

◆ SqlVariant() [5/8]

◆ SqlVariant() [6/8]

◆ SqlVariant() [7/8]

◆ SqlVariant() [8/8]

Member Function Documentation

◆ operator=() [1/3]

◆ operator=() [2/3]

◆ operator=() [3/3]

◆ IsNull()

◆ Is()

◆ Get()

◆ ValueOr()

◆ TryGetBool()

◆ TryGetInt8()

◆ TryGetShort()

◆ TryGetUShort()

◆ TryGetInt()

◆ TryGetUInt()

◆ TryGetLongLong()

◆ TryGetULongLong()

◆ TryGetStringView()

◆ TryGetUtf16StringView()

◆ TryGetDate()

◆ operator==()

◆ operator!=()

◆ TryGetTime()

◆ TryGetDateTime()

◆ TryGetGuid()

◆ TryGetNumeric()

◆ TryGetBinary()

Member Data Documentation

◆ value