7.10.1 Database Objects
The database objects returned by open() provide the methods
common to all the DBM-style databases. The following methods are
available in addition to the standard methods.
- first()
-
It's possible to loop over every key in the database using this method
and the 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.
- last()
-
Return the last key in a database traversal. This may be used to
begin a reverse-order traversal; see previous().
- next(key)
-
Returns the key that follows key in the traversal. The
following code prints every key in the database
db
, without
having to create a list in memory that contains them all:
k = db.first()
while k != None:
print k
k = db.next(k)
- previous(key)
-
Return the key that comes before key in a forward-traversal of
the database. In conjunction with last(), this may be used
to implement a reverse-order traversal.
- sync()
-
This method forces any unwritten data to be written to the disk.
See About this document... for information on suggesting changes.