Berkeley DB Reference Guide: Database open

Berkeley DB Reference Guide:
Access Methods

Database open

The DB->open method opens a database, and takes five arguments:

( DB->open 는 디비를 연다.인자5개를 가진다.)

file: The name of the file to be opened.

(열릴 파일)

database

An optional database name. (옵션적 디비이름)

type

The type of database to open. This value will be one of the four access methods Berkeley DB supports: DB_BTREE, DB_HASH, DB_QUEUE or DB_RECNO, or the special value DB_UNKNOWN, which allows you to open an existing file without knowing its type.

(열릴 디비의 타입,엑세스메소드중의 하나가 된다. DB_BTREE, DB_HASH, DB_QUEUE or DB_RECNO,거나 타입정보없이 기존의 파일을 여는 DB_UNKNOWN)

mode

The permissions to give to any created file. (생성파일에 줄 퍼미션)

There are a few flags that you can set to customize open:

(오픈을 커스터마이징하기 위해 설정할 수 있는 여러 플래그들)

DB_CREATE: Create the underlying database and any necessary physical files.
DB_NOMMAP: Do not map this database into process memory.
DB_RDONLY: Treat the data base as read-only.
DB_THREAD: The returned handle is free-threaded, that is, it can be used simultaneously by multiple threads within the process.
DB_TRUNCATE: Physically truncate the underlying database file, discarding all databases it contained. Underlying filesystem primitives are used to implement this flag. For this reason it is only applicable to the physical file and cannot be used to discard individual databases from within physical files.
DB_UPGRADE: Upgrade the database format as necessary.

Berkeley DB Reference Guide:Access Methods

Database open

Berkeley DB Reference Guide:
Access Methods