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diff --git a/Doc/library/dbhash.rst b/Doc/library/dbhash.rst deleted file mode 100644 index aadb14f..0000000 --- a/Doc/library/dbhash.rst +++ /dev/null @@ -1,114 +0,0 @@ - -:mod:`dbhash` --- DBM-style interface to the BSD database library -================================================================= - -.. module:: dbhash - :synopsis: DBM-style interface to the BSD database library. -.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org> - - -.. index:: module: bsddb - -The :mod:`dbhash` module provides a function to open databases using the BSD -``db`` library. This module mirrors the interface of the other Python database -modules that provide access to DBM-style databases. The :mod:`bsddb` module is -required to use :mod:`dbhash`. - -This module provides an exception and a function: - - -.. exception:: error - - Exception raised on database errors other than :exc:`KeyError`. It is a synonym - for :exc:`bsddb.error`. - - -.. function:: open(path[, flag[, mode]]) - - Open a ``db`` database and return the database object. The *path* argument is - the name of the database file. - - The *flag* argument can be: - - +---------+-------------------------------------------+ - | Value | Meaning | - +=========+===========================================+ - | ``'r'`` | Open existing database for reading only | - | | (default) | - +---------+-------------------------------------------+ - | ``'w'`` | Open existing database for reading and | - | | writing | - +---------+-------------------------------------------+ - | ``'c'`` | Open database for reading and writing, | - | | creating it if it doesn't exist | - +---------+-------------------------------------------+ - | ``'n'`` | Always create a new, empty database, open | - | | for reading and writing | - +---------+-------------------------------------------+ - - For platforms on which the BSD ``db`` library supports locking, an ``'l'`` - can be appended to indicate that locking should be used. - - The optional *mode* parameter is used to indicate the Unix permission bits that - should be set if a new database must be created; this will be masked by the - current umask value for the process. - - -.. seealso:: - - Module :mod:`anydbm` - Generic interface to ``dbm``\ -style databases. - - Module :mod:`bsddb` - Lower-level interface to the BSD ``db`` library. - - Module :mod:`whichdb` - Utility module used to determine the type of an existing database. - - -.. _dbhash-objects: - -Database Objects ----------------- - -The database objects returned by :func:`open` provide the methods common to all -the DBM-style databases and mapping objects. The following methods are -available in addition to the standard methods. - - -.. method:: dbhash.first() - - It's possible to loop over every key/value pair in the database using this - method and the :meth:`next` method. The traversal is ordered by the databases - internal hash values, and won't be sorted by the key values. This method - returns the starting key. - - -.. method:: dbhash.last() - - Return the last key/value pair in a database traversal. This may be used to - begin a reverse-order traversal; see :meth:`previous`. - - -.. method:: dbhash.next() - - Returns the key next key/value pair in a database traversal. The following code - prints every key in the database ``db``, without having to create a list in - memory that contains them all:: - - print(db.first()) - for i in range(1, len(db)): - print(db.next()) - - -.. method:: dbhash.previous() - - Returns the previous key/value pair in a forward-traversal of the database. In - conjunction with :meth:`last`, this may be used to implement a reverse-order - traversal. - - -.. method:: dbhash.sync() - - This method forces any unwritten data to be written to the disk. - |