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A little bit more text on the tutorial

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hofmockel 2014-02-02 17:25:46 +01:00
parent 47da4653c9
commit b417a564ec
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docs/tutorial/index.rst
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@ -165,8 +165,13 @@ MergeOperator
=============
Merge operators are useful for efficient read-modify-write operations.
For more details see `Merge Operator <https://github.com/facebook/rocksdb/wiki/Merge-Operator>`_
The simple Associative merge ::
A python merge operator must either implement the
:py:class:`rocksdb.interfaces.AssociativeMergeOperator` or
:py:class:`rocksdb.interfaces.MergeOperator` interface.
The following example python merge operator implements a counter ::
class AssocCounter(rocksdb.interfaces.AssociativeMergeOperator):
def merge(self, key, existing_value, value):
@ -195,8 +200,10 @@ PrefixExtractor
According to `Prefix API <https://github.com/facebook/rocksdb/wiki/Proposal-for-prefix-API>`_
a prefix_extractor can reduce IO for scans within a prefix range.
The following example presents a prefix extractor of a static size. So always
the first 5 bytes are used as the prefix ::
A python prefix extractor must implement the :py:class:`rocksdb.interfaces.SliceTransform` interface.
The following example presents a prefix extractor of a static size.
So always the first 5 bytes are used as the prefix ::
class StaticPrefix(rocksdb.interfaces.SliceTransform):
def name(self):