lmdb::basic_table< K, V > Struct Template Reference

Helper for grouping typical LMDB DBI options when key and value are fixed types. More...

#include <table.h>

Inheritance diagram for lmdb::basic_table< K, V >:

Collaboration diagram for lmdb::basic_table< K, V >:

Public Types
using	key_type = K
using	value_type = V

Public Member Functions
constexpr	basic_table (const char *name, unsigned flags=0, MDB_cmp_func value_cmp=nullptr) noexcept
Public Member Functions inherited from lmdb::table
expect< MDB_dbi >	open (MDB_txn &write_txn) const noexcept

Static Public Member Functions
static constexpr unsigned	compute_flags (const unsigned flags) noexcept
template<typename U , typename F = U, std::size_t offset = 0>
static expect< F >	get_value (MDB_val value) noexcept
template<typename D >
static expect< key_stream< K, V, D > >	get_key_stream (std::unique_ptr< MDB_cursor, D > cur) noexcept
template<typename D >
static expect< value_stream< V, D > >	get_value_stream (K const &key, std::unique_ptr< MDB_cursor, D > cur) noexcept

Additional Inherited Members
Public Attributes inherited from lmdb::table
char const *const	name
const unsigned	flags
MDB_cmp_func *const	key_cmp
MDB_cmp_func *const	value_cmp

Detailed Description

template<typename K, typename V>
struct lmdb::basic_table< K, V >

Helper for grouping typical LMDB DBI options when key and value are fixed types.

Member Typedef Documentation

key_type

template<typename K , typename V >

using lmdb::basic_table< K, V >::key_type = K

value_type

template<typename K , typename V >

using lmdb::basic_table< K, V >::value_type = V

Constructor & Destructor Documentation

basic_table()

template<typename K , typename V >

constexpr lmdb::basic_table< K, V >::basic_table ( const char *  name, unsigned  flags = 0, MDB_cmp_func  value_cmp = nullptr  )

inlineexplicitconstexprnoexcept

Member Function Documentation

compute_flags()

template<typename K , typename V >

static constexpr unsigned lmdb::basic_table< K, V >::compute_flags ( const unsigned  flags )

inlinestaticconstexprnoexcept

Returns

Additional LMDB flags based on flags value.

get_key_stream()

template<typename K , typename V >

template<typename D >

static expect<key_stream<K, V, D> > lmdb::basic_table< K, V >::get_key_stream ( std::unique_ptr< MDB_cursor, D >  cur )

inlinestaticnoexcept

Precondition

cur != nullptr.

Parameters

cur	Active cursor on table. Returned in object on success, otherwise destroyed.

Returns

A handle to the first key/value in the table linked to cur or an empty key_stream.

get_value()

template<typename K , typename V >

template<typename U , typename F = U, std::size_t offset = 0>

static expect<F> lmdb::basic_table< K, V >::get_value ( MDB_val  value )

inlinestaticnoexcept

Template Parameters

U	must be same as V; used for sanity checking.
F	is the type within U that is being extracted.
offset	to F within U.

Note

If using F and offset to retrieve a specific field, use ELECTRONEUM_FIELD macro in src/lmdb/util.h which calculates the offset automatically.

Returns

Value of type F at offset within value which has type U.

get_value_stream()

template<typename K , typename V >

template<typename D >

static expect<value_stream<V, D> > lmdb::basic_table< K, V >::get_value_stream ( K const &  key, std::unique_ptr< MDB_cursor, D >  cur  )

inlinestaticnoexcept

Precondition

cur != nullptr.

Parameters

cur	Active cursor on table. Returned in object on success, otherwise destroyed.

Returns

A handle to the first value at key in the table linked to cur or an empty value_stream.

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

• src/lmdb/table.h