pysqllike documentation
=======================

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**Links:** `pypi <https://pypi.python.org/pypi/pysqllike/>`_,
`github <https://github.com/sdpython/pysqllike/>`_,
`documentation <http://www.xavierdupre.fr/app/pysqllike/helpsphinx/index.html>`_,
`wheel <http://www.xavierdupre.fr/site2013/index_code.html#pysqllike>`_,
:ref:`l-README`,
:ref:`blog <ap-main-0>`

What is it?
-----------

Writing a map/reduce job
(using `PIG <https://pig.apache.org/>`_ for example),
usually requires to switch from local files to remote files
(on `Hadoop <http://hadoop.apache.org/>`_).
On way to work is extract a small sample of the data which will be processed
by a map/reduce job. The job is then locally developped. And when it works,
it is run on a parallized environment.

The goal of this extension is allow the implementation of
this job using Python syntax as follows:

::

    def myjob(input):
        iter = input.select (input.age, input.nom, age2 = input.age2*input.age2)
        wher = iter.where( (iter.age > 60).Or(iter.age < 25))
        return wher

    input = IterRow (None, [ {"nom": 10}, {"jean": 40} ] )
    output = myjob(input)

When the job is ready, it can be translated into a
`PIG <https://pig.apache.org/>`_ job::

    input = LOAD '...' USING PigStorage('\t') AS (nom, age);
    iter = FOREACH input GENERATE age, nom, age*age AS age2 ;
    wher = FILTER iter BY age > 60 or age < 25 ;
    STORE wher INTO '...' USING PigStorage();

It should also be translated into
`SQL <http://fr.wikipedia.org/wiki/Structured_Query_Language>`_.
The module relies on `ast <https://docs.python.org/3/library/ast.html>`_
and intents to produce a streaming function
:math:`f : stream \rightarrow stream`. The project
is discontinued.

Installation
------------

``pip install pysqllike``

Functionalities
---------------

* not yet ready

Quick start
-----------

.. toctree::
    :maxdepth: 1

    all_notebooks
    blog/blogindex

Indices and tables
------------------

+----------------------+---------------------+---------------------+--------------------+------------------------+------------------------------------------------+
| :ref:`l-modules`     |  :ref:`l-functions` | :ref:`l-classes`    | :ref:`l-methods`   | :ref:`l-staticmethods` | :ref:`l-properties`                            |
+----------------------+---------------------+---------------------+--------------------+------------------------+------------------------------------------------+
| :ref:`modindex`      |  :ref:`l-example`   | :ref:`search`       | :ref:`l-license`   | :ref:`l-changes`       | :ref:`l-README`                                |
+----------------------+---------------------+---------------------+--------------------+------------------------+------------------------------------------------+
| :ref:`genindex`      |  :ref:`l-FAQ`       | :ref:`l-notebooks`  |                    | :ref:`l-statcode`      | `Unit Test Coverage <coverage/index.html>`_    |
+----------------------+---------------------+---------------------+--------------------+------------------------+------------------------------------------------+

Navigation
----------

.. toctree::
    :maxdepth: 1

    indexmenu