XX. DBM Functions


These functions allow you to store records stored in a dbm-style database. This type of database (supported by the Berkeley DB, GDBM, and some system libraries, as well as a built-in flatfile library) stores key/value pairs (as opposed to the full-blown records supported by relational databases).

Megjegyzés: However, dbm support is deprecated and you are encourged to use the Database (dbm-style) abstraction layer functions instead.


To use this functions you have to compile PHP with support for an underlying database. See the list of supported Databases.


In order to use these functions, you must compile PHP with dbm support by using the --with-db option. In addtion you must ensure support for an underlying database or you can use some sytem libraries.

Futásidejű beállítások

Ez a kiterjesztés semmilyen konfigurációs beállításokat nem definiál.

Erőforrás típusok

The function dbmopen() returns an database identifier which is used by the other dbm-functions.

Előre definiált állandók

Ez a kiterjesztés semmilyen konstans értéket nem definiál.


Példa 1. DBM example

$dbm = dbmopen ("lastseen", "w");
if (dbmexists ($dbm, $userid)) {
    $last_seen = dbmfetch ($dbm, $userid);
} else {
    dbminsert ($dbm, $userid, time());
dbmreplace ($dbm, $userid, time());
dbmclose ($dbm);

dblist --  Describes the DBM-compatible library being used
dbmclose -- Closes a dbm database
dbmdelete --  Deletes the value for a key from a DBM database
dbmexists --  Tells if a value exists for a key in a DBM database
dbmfetch --  Fetches a value for a key from a DBM database
dbmfirstkey --  Retrieves the first key from a DBM database
dbminsert --  Inserts a value for a key in a DBM database
dbmnextkey --  Retrieves the next key from a DBM database
dbmopen -- Opens a DBM database
dbmreplace --  Replaces the value for a key in a DBM database