vtab< Derived > Class Template Reference

Base class for virtual table object implementations. More...

Inheritance diagram for vtab< Derived >:

Classes
class	cursor
	Base class for cursors. More...
struct	create_t
	Marker type that marks the constructor of Derived to be used to create a new table. More...
struct	connect_t
	Marker type that tells the constructor of Derived to be used to connect to an existing table. More...

Public Types
using	constructor_data_type = void
	Type of data passed via create_module to the constructor(s).
using	index_data_type = void
	Type of data stored in index_info and passed between best_index and filter.

Public Member Functions
template<class D = Derived>
	SQLITEPP_ENABLE_IFP (static,(std::is_pointer_v< typename D::constructor_data_type >), void) create_module(database &db
	Register a virtual table implementation with a database connection.

Static Public Member Functions
static void	create_module (database &db, const string_param &name)
	Register a virtual table implementation with a database connection.

Public Attributes
const string_param &	name
const string_param D::constructor_data_type	data
const string_param D::constructor_data_type void(*	destructor )(typename D::constructor_data_type) noexcept

Protected Member Functions
	vtab ()
	This class is default constructible only by derived classes.
	vtab (const vtab &)=delete
	You cannot copy (or move) this class.
vtab &	operator= (const vtab &)=delete
	You cannot assign this class.
	~vtab ()
	This class is destructible only by derived classes.

Detailed Description

template<class Derived>
class thinsqlitepp::vtab< Derived >

Base class for virtual table object implementations.

This class greatly simplifies development of virtual tables by encapsulating management of sqlite3_module, providing type safety, error handling and RAII and reasonable defaults.

It is intended to be used as CRTP base class for your own virtual table implementations.

Important

This documentation only describes the base class interface. Please refer to Implementing Virtual Tables for detailed information about how to create classes derived from vtab to implement virtual tables.

#include <thinsqlitepp/vtab.hpp>

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Class Documentation

thinsqlitepp::vtab::create_t

struct thinsqlitepp::vtab::create_t

template<class Derived>
struct thinsqlitepp::vtab< Derived >::create_t

Marker type that marks the constructor of Derived to be used to create a new table.

thinsqlitepp::vtab::connect_t

struct thinsqlitepp::vtab::connect_t

template<class Derived>
struct thinsqlitepp::vtab< Derived >::connect_t

Marker type that tells the constructor of Derived to be used to connect to an existing table.

Member Typedef Documentation

constructor_data_type

template<class Derived>

using constructor_data_type = void

Type of data passed via create_module to the constructor(s).

You can override this default by declaring a different typedef in your derived class

The default is void, meaning no data is stored and passed

index_data_type

template<class Derived>

using index_data_type = void

Type of data stored in index_info and passed between best_index and filter.

You can override this default by declaring a different typedef in your derived class.

The default is void, meaning no data is stored and passed

Member Function Documentation

create_module()

template<class Derived>

void create_module ( database & db, const string_param & name )

inlinestatic

Register a virtual table implementation with a database connection.

Equivalent to sqlite3_create_module_v2

If constructor_data_type is not void using this method causes nullptr to be passed to derived class constructor.

Parameters

db	database to register the implementation with
name	module name

SQLITEPP_ENABLE_IFP()

template<class Derived>

template<class D = Derived>

SQLITEPP_ENABLE_IFP	(	static	,
		(std::is_pointer_v< typename D::constructor_data_type >)	,
		void	) &

Register a virtual table implementation with a database connection.

Equivalent to sqlite3_create_module_v2

This overload is available if constructor_data_type is not void.

Template Parameters

D	Defers resolution of nested data types declared in derived class. This is an internal implementation detail - never specify it explicitly.

Parameters

db	database to register the implementation with
name	module name
data	data to be passed to your derived class constructor. Can be nullptr. You can change the type of the data by re-defining constructor_data_type in your derived class.
destructor	an optional destructor function for the data pointer. Can be nullptr.