isabella232 / cpy-leveldb Goto Github PK

cpy-leveldb: Python bindings for LevelDB using leveldb c api
(http://code.google.com/p/leveldb/)
author: Fu Haiping ([email protected])

1. Build Instructions
---------------------

First of all, you need to build the included snappy and  leveldb library.

1.1 Build Snappy
-----------------
$ cd snappy
$ ./configure && make && make install

1.2 Build LevelDB
-----------------
$ cd leveldb
$ make 

1.3 Then, build the extension itself
------------------------------------
$ python setup.py build


2. Example Usage
----------------

>>> import leveldb
>>> db = leveldb.LevelDB("/tmp/leveldb")
>>> db.Put("1", "111")
>>> db.Put("2", "222")
>>> db.Put("3", "333")
>>> db.Get("1")
'111'
>>> db.Get("3")
'333'
>>> db.Get("2")
'222'
>>> batch = leveldb.WriteBatch()
>>> for i in xrange(20):
...     batch.Put(str(i), "hello world %i" % i)
... 
>>> db.Get("2")
'222'
>>> db.Get("5")
''
>>> db.Write(batch)
>>> db.Get("5")
'hello world 5'
>>> db.Get("2")
'hello world 2'
>>> iter = leveldb.Iterator(db)
Iterator_init executed.
>>> iter.First()
>>> iter.Key()
'0'
>>> iter.Value()
'hello world 0'
>>> iter.Last()
>>> iter.Key()
'9'
>>> iter.Value()
'hello world 9'
>>> iter.First()
>>> iter.Next()
>>> iter.Key()
'1'
>>> iter.Next()
>>> iter.Key()
'10'
>>> iter.Next()
>>> iter.Key()
'11'
>>> iter.Value()
'hello world 11'
>>> db.Put("1", "111")
>>> db.Put("2", "222")
>>> db.Put("3", "333")
>>> db.Get("1")
'111'
>>> snap = leveldb.Snapshot(db)
Snapshot_init executed.
>>> db.Delete("1")
>>> db.Get("1")
''
>>> snap.Set()
>>> db.Get("1")
'111'
>>> snap.Reset()
>>> db.Get("1")
''
>>> snap.Release()