I recently configured psycopg2 on a windows machine. The easiest install is using a windows executable binary. You can find it at http://stickpeople.com/projects/python/win-psycopg/.

To install the native binary in a virtual envrionment, use easy_install:

C:virtualenvScripts> activate.bat
(virtualenv) C:virtualenvScripts> easy_install psycopg2-2.5.win32-py2.7-pg9.2.4-release.exe

I’ve done this before where in windows you install first into your base python installation.

Then, you manually copy the installed psycopg2 to the virtualenv install.

It’s not pretty, but it works.

On windows XP you get this error if postgres is not installed …

If you using Mac OS, you should install PostgreSQL from source.
After installation is finished, you need to add this path using:

export PATH=/local/pgsql/bin:$PATH

or you can append the path like this:

export PATH=.../:usr/local/pgsql/bin

in your .profile file or .zshrc file.

This maybe vary by operating system.

You can follow the installation process from http://www.thegeekstuff.com/2009/04/linux-postgresql-install-and-configure-from-source/

I’ve been battling with this for days, and have finally figured out how to get the “pip install psycopg2” command to run in a virtualenv in Windows (running Cygwin).

I was hitting the “pg_config executable not found.” error, but I had already downloaded and installed postgres in Windows. It installed in Cygwin as well; running “which pg_config” in Cygwin gave “/usr/bin/pg_config”, and running “pg_config” gave sane output — however the version installed with Cygwin is:

VERSION = PostgreSQL 8.2.11

This won’t work with the current version of psycopg2, which appears to require at least 9.1. When I added “c:Program FilesPostgreSQL9.2bin” to my Windows path, the Cygwin pip installer was able to find the correct version of PostgreSQL, and I was able to successfully install the module using pip. (This is probably preferable to using the Cygwin version of PostgreSQL anyway, as the native version will run much quicker).

For Python 3 you should use sudo apt-get install libpq-dev python3-dev under Debian.

On CentOS, you need the postgres dev packages:

sudo yum install python-devel postgresql-devel

That was the solution on CentOS 6 at least.

Besides installing the required packages, I also needed to manually add PostgreSQL bin directory to PATH.
$vi ~/.bash_profile
Add PATH=/usr/pgsql-9.2/bin:$PATH before export PATH.
$source ~/.bash_profile
$pip install psycopg2

I installed Postgresql92 using the RedHat / CentOS repository on PG’s downloads site http://www.postgresql.org/download/linux/redhat/

To get pg_config, I had to add /usr/pgsql-9.2/bin to PATH.

if you’re on a mac you can use homebrew

brew install postgresql

And all other options are here: http://www.postgresql.org/download/macosx/

Good luck

On Mac Mavericks with Postgres.app version 9.3.2.0 RC2 I needed to use the following code after installing Postgres:

sudo PATH=$PATH:/Applications/Postgres.app/Contents/Versions/9.3/bin pip install psycopg2

This is what worked for me (On RHEL, CentOS:

sudo yum install postgresql postgresql-devel python-devel

And now include the path to your postgresql binary dir with you pip install:

sudo PATH=$PATH:/usr/pgsql-9.3/bin/ pip install psycopg2

Make sure to include the correct path. Thats all 🙂

UPDATE: For python 3, please install python3-devel instead of python-devel

For lowly Windows users were stuck having to install psycopg2 from the link below, just install it to whatever Python installation you have setup. It will place the folder named “psycopg2” in the site-packages folder of your python installation.

After that, just copy that folder to the site-packages directory of your virtualenv and you will have no problems.

here is the link you can find the executable to install psycopg2

http://www.lfd.uci.edu/~gohlke/pythonlibs/

The answers so far are too much like magic recipes. The error that you received tells you that pip cannot find a needed part of the PostgreSQL Query library. Possibly this is because you have it installed in a non-standard place for your OS which is why the message suggests using the –pg-config option.

But a more common reason is that you don’t have libpq installed at all. This commonly happens on machines where you do NOT have PostgreSQL server installed because you only want to run client apps, not the server itself. Each OS/distro is different, for instance on Debian/Ubuntu you need to install libpq-dev. This allows you to compile and link code against the PostgreSQL Query library.

Most of the answers also suggest installing a Python dev library. Be careful. If you are only using the default Python installed by your distro, that will work, but if you have a newer version, it could cause problems. If you have built Python on this machine then you already have the dev libraries needed for compiling C/C++ libraries to interface with Python. As long as you are using the correct pip version, the one installed in the same bin folder as the python binary, then you are all set. No need to install the old version.

Psycopg2 Depends on Postgres Libraries.
On Ubuntu You can use:

apt-get install libpq-dev

Then:

pip install psycopg2

On OpenSUSE 13.2, this fixed it:

sudo zypper in postgresql-devel 

On Debian/Ubuntu:

First install and build dependencies of psycopg2 package:

# apt-get build-dep python-psycopg2

Then in your virtual environment, compile and install psycopg2 module:

(env)$ pip install psycopg2

On Ubuntu I just needed the postgres dev package:

sudo apt-get install postgresql-server-dev-all

*Tested in a virtualenv

I could install it in a windows machine and using Anaconda/Spyder with python 2.7 through the following commands:

 !pip install psycopg2

Then to establish the connection to the database:

 import psycopg2
 conn = psycopg2.connect(dbname='dbname',host='host_name',port='port_number', user='user_name', password='password')

In Arch base distributions:

sudo pacman -S python-psycopg2
pip2 install psycopg2  # Use pip or pip3 to python3

On Fedora 24: For Python 3.x

sudo dnf install postgresql-devel python3-devel

sudo dnf install redhat-rpm-config

Activate your Virtual Environment:

pip install psycopg2

On OSX 10.11.6 (El Capitan)

brew install postgresql
PATH=$PATH:/Library/PostgreSQL/9.4/bin pip install psycopg2

On OSX with macports:

sudo port install postgresql96
export PATH=/opt/local/lib/postgresql96/bin:$PATH

if pip is not working than you can download .whl file from here https://pypi.python.org/pypi/psycopg2
extract it..
than python setup.py install

Before you can install psycopg2 you will need to install the python-dev package.

If you’re working from Linux (and possibly other systems but i can’t speak from experience) you will need to make sure to be quite exact about what version of python your running when installing the dev package.

For example when I used the command:

sudo apt-get install python3-dev

I still ran into the same error when trying to

pip install psycopg2

As I am using python 3.7 I needed to use the command

sudo apt-get install python3.7-dev

Once I did this I ran into no more issues. Obviously if your on python version 3.5 you would change that 7 to a 5.

I was having this problem, the main reason was with 2 equal versions installed. One by postgres.app and one by HomeBrew.

If you choose to keep only the APP:

brew unlink postgresql
pip3 install psycopg2

On macOS Mojave make sure you on newest update with Command Line Tools 10.3 – that worked for me – updated it with Software Update, previous version of Command Line Tools on Mojave did not work for me.

On windows this is how it works
On the command prompt after installing flask via pip in virtual environment, run this command

>pip install psycopg2

Check this

Make sure Postgres is installed and PATH is updated before running pip install psycopg2

export PATH="$PATH:/Applications/Postgres.app/Contents/Versions/12/bin"

Every time I run into this problem this seems to work for me.

pip install psycopg2==2.7.5

For MacOS,

Use the below command to install psycopg2, works like charm!!!

env LDFLAGS="-I/usr/local/opt/openssl/include -L/usr/local/opt/openssl/lib" pip install psycopg2

Installation on MacOS

Following are the steps, which worked for me and my team members while installing psycopg2 on Mac OS Big Sur and which we have extensively tested for Big Sur. Before starting make sure you have the Xcode command-line tool installed. If not, then install it from the Apple Developer site. The below steps assume you have homebrew installed. If you have not installed homebrew then install it. Last but not the least, it also assumes you already have PostgreSQL installed in your system, if not then install it. Different people have different preferences but the default installation method on the official PostgreSQL site via Enterprise DB installer is the best method for the majority of people.

• Put up the linkage to pg_config file in your .zshrc file by:
  export PATH="$PATH:/Library/PostgreSQL/12/bin:$PATH". This way you are having linkage with the pg_config file in the /Library/PostgreSQL/12/bin folder. So if your PostgreSQL installation is via other means, like Postgres.app or Postgres installation via homebrew, then you need to have in your .zshrc file the link to pg_config file from the bin folder of that PostgreSQL installation as psycopg2 relies on that.

• Install OpenSSL via Homebrew using the command brew install openssl. The reason for this is that libpq, the library which is the basis of psycopg2, uses openssl – psycopg2 doesn’t use it directly. After installing put the following commands in your .zshrc file:

  • export PATH="/usr/local/opt/[email protected]/bin:$PATH"
  • export LDFLAGS="-L/usr/local/opt/[email protected]/lib"
  • export CPPFLAGS="-I/usr/local/opt/[email protected]/include"
    By doing this you are creating necessary linkages in your directory. These commands are suggested by brew while you install openssl and have been directly picked up from there.

• Now comes the most important step, which is to install libpq using the command brew install libpq. This installs libpq library. As per the documentation

libpq is the C application programmer’s interface to PostgreSQL. libpq is a set of library functions that allow client programs to pass queries to the PostgreSQL backend server and to receive the results of these queries.

• Link libpq using brew link libpq, if this doesn’t work then use the command: brew link libpq --force.
• Also put in your .zshrc file the following
  export PATH="/usr/local/opt/libpq/bin:$PATH". This creates all the necessary linkages for libpq library .
• Now restart the terminal or use the following command source ~/.zshrc.

  This works even when you are working in conda environment.

  N.B. pip install psycopg2-binaryshould be avoided because as per the developers of the psycopg2 library

The use of the -binary packages in production is discouraged because in the past they proved unreliable in multithread environments. This might have been fixed in more recent versions but I have never managed to reproduce the failure.

I had this error only with Python2. Immediately I upgraded my virtual environment to Python3.8, the error was no more.

Run below commands and you should be fine

$ apt-get update
$ apt install python3-dev libpq-dev
$ pip3 install psycopg2