NCBI C++ ToolKit
Modules | Classes | Typedefs
LMDB API

OpenLDAP Lightning Memory-Mapped Database Manager. More...

+ Collaboration diagram for LMDB API:

Modules

 Versioning
 
 Environment Flags
 
 Database Flags
 
 Write Flags
 

Classes

struct  MDB_val
 Generic structure used for passing keys and data in and out of the database. More...
 

Typedefs

typedef struct MDB_env MDB_env
 Opaque structure for a database environment. More...
 
typedef struct MDB_txn MDB_txn
 Opaque structure for a transaction handle. More...
 
typedef unsigned int MDB_dbi
 A handle for an individual database in the DB environment. More...
 
typedef struct MDB_cursor MDB_cursor
 Opaque structure for navigating through a database. More...
 
typedef struct MDB_val MDB_val
 Generic structure used for passing keys and data in and out of the database. More...
 
typedef int() MDB_cmp_func(const MDB_val *a, const MDB_val *b)
 A callback function used to compare two keys in a database. More...
 
typedef void() MDB_rel_func(MDB_val *item, void *oldptr, void *newptr, void *relctx)
 A callback function used to relocate a position-dependent data item in a fixed-address database. More...
 

Detailed Description

OpenLDAP Lightning Memory-Mapped Database Manager.

Typedef Documentation

◆ MDB_cmp_func

typedef int() MDB_cmp_func(const MDB_val *a, const MDB_val *b)

A callback function used to compare two keys in a database.

Definition at line 263 of file lmdb.h.

◆ MDB_cursor

typedef struct MDB_cursor MDB_cursor

Opaque structure for navigating through a database.

Definition at line 241 of file lmdb.h.

◆ MDB_dbi

typedef unsigned int MDB_dbi

A handle for an individual database in the DB environment.

Definition at line 241 of file lmdb.h.

◆ MDB_env

typedef struct MDB_env MDB_env

Opaque structure for a database environment.

A DB environment supports multiple databases, all residing in the same shared-memory map.

Definition at line 188 of file lmdb.h.

◆ MDB_rel_func

typedef void() MDB_rel_func(MDB_val *item, void *oldptr, void *newptr, void *relctx)

A callback function used to relocate a position-dependent data item in a fixed-address database.

The newptr gives the item's desired address in the memory map, and oldptr gives its previous address. The item's actual data resides at the address in item. This callback is expected to walk through the fields of the record in item and modify any values based at the oldptr address to be relative to the newptr address.

Parameters
[in,out]itemThe item that is to be relocated.
[in]oldptrThe previous address.
[in]newptrThe new address to relocate to.
[in]relctxAn application-provided context, set by mdb_set_relctx().

The newptr gives the item's desired address in the memory map, and oldptr gives its previous address. The item's actual data resides at the address in item. This callback is expected to walk through the fields of the record in item and modify any values based at the oldptr address to be relative to the newptr address.

Parameters
[in,out]itemThe item that is to be relocated.
[in]oldptrThe previous address.
[in]newptrThe new address to relocate to.
[in]relctxAn application-provided context, set by mdb_set_relctx().

Definition at line 279 of file lmdb.h.

◆ MDB_txn

typedef struct MDB_txn MDB_txn

Opaque structure for a transaction handle.

All database operations require a transaction handle. Transactions may be read-only or read-write.

Definition at line 188 of file lmdb.h.

◆ MDB_val

typedef struct MDB_val MDB_val

Generic structure used for passing keys and data in and out of the database.

Values returned from the database are valid only until a subsequent update operation, or the end of the transaction. Do not modify or free them, they commonly point into the database itself.

Key sizes must be between 1 and mdb_env_get_maxkeysize() inclusive. The same applies to data sizes in databases with the MDB_DUPSORT flag. Other data items can in theory be from 0 to 0xffffffff bytes long.

Modified on Wed May 29 18:40:14 2024 by modify_doxy.py rev. 669887