Psycopg is the most popular PostgreSQL database adapter for the Python programming language. Its main features are the complete implementation of the Python DB API 2.0 specification and the thread safety (several threads can share the same connection). It was designed for heavily multi-threaded applications that create and destroy lots of cursors and make a large number of concurrent "INSERT"s or "UPDATE"s.
Psycopg 2 is mostly implemented in C as a libpq wrapper, resulting in being both efficient and secure. It features client-side and server-side cursors, asynchronous communication and notifications, "COPY TO/COPY FROM" support. Many Python types are supported out-of-the-box and adapted to matching PostgreSQL data types; adaptation can be extended and customized thanks to a flexible objects adaptation system.
Psycopg 2 is both Unicode and Python 3 friendly.
.. Note::
The psycopg2 package is still widely used and actively maintained, but it
is not expected to receive new features.
`Psycopg 3`__ is the evolution of psycopg2 and is where `new features are
being developed`__: if you are starting a new project you should probably
start from 3!
.. __: https://pypi.org/project/psycopg/
.. __: https://www.psycopg.org/psycopg3/docs/index.html
Documentation is included in the doc
directory and is available online
__.
.. __: https://www.psycopg.org/docs/
For any other resource (source code repository, bug tracker, mailing list)
please check the project homepage
__.
.. __: https://psycopg.org/
Building Psycopg requires a few prerequisites (a C compiler, some development
packages): please check the install and the faq documents in the doc
dir
or online for the details.
If prerequisites are met, you can install psycopg like any other Python
package, using pip
to download it from PyPI_::
$ pip install psycopg2
or using setup.py
if you have downloaded the source package locally::
$ python setup.py build
$ sudo python setup.py install
You can also obtain a stand-alone package, not requiring a compiler or
external libraries, by installing the psycopg2-binary
_ package from PyPI::
$ pip install psycopg2-binary
The binary package is a practical choice for development and testing but in production it is advised to use the package built from sources.
.. _PyPI: https://pypi.org/project/psycopg2/ .. _psycopg2-binary: https://pypi.org/project/psycopg2-binary/ .. _install: https://www.psycopg.org/docs/install.html#install-from-source .. _faq: https://www.psycopg.org/docs/faq.html#faq-compile
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