11.12. dumbdbm — Portable DBM implementation¶
Note
The dumbdbm module has been renamed to dbm.dumb in Python 3.
The 2to3 tool will automatically adapt imports when converting your
sources to Python 3.
Note
The dumbdbm module is intended as a last resort fallback for the
anydbm module when no more robust module is available. The dumbdbm
module is not written for speed and is not nearly as heavily used as the other
database modules.
The dumbdbm module provides a persistent dictionary-like interface which
is written entirely in Python. Unlike other modules such as gdbm and
bsddb, no external library is required. As with other persistent
mappings, the keys and values must always be strings.
The module defines the following:
-
exception
dumbdbm.error¶ Raised on dumbdbm-specific errors, such as I/O errors.
KeyErroris raised for general mapping errors like specifying an incorrect key.
-
dumbdbm.open(filename[, flag[, mode]])¶ Open a dumbdbm database and return a dumbdbm object. The filename argument is the basename of the database file (without any specific extensions). When a dumbdbm database is created, files with
.datand.dirextensions are created.The optional flag argument is currently ignored; the database is always opened for update, and will be created if it does not exist.
The optional mode argument is the Unix mode of the file, used only when the database has to be created. It defaults to octal
0666(and will be modified by the prevailing umask).Changed in version 2.2: The mode argument was ignored in earlier versions.
In addition to the dictionary-like methods, dumbdm objects
provide the following method:
-
dumbdbm.close()¶ Close the
dumbdmdatabase.
See also
- Module
anydbm - Generic interface to
dbm-style databases. - Module
dbm - Similar interface to the DBM/NDBM library.
- Module
gdbm - Similar interface to the GNU GDBM library.
- Module
shelve - Persistence module which stores non-string data.
- Module
whichdb - Utility module used to determine the type of an existing database.
11.12.1. Dumbdbm Objects¶
In addition to the methods provided by the UserDict.DictMixin class,
dumbdbm objects provide the following methods.
