If you are working with PostgreSQL and trying to install a library or extension that requires it, you may encounter an error message saying “pg_config executable not found.” This error means that the pg_config utility, which is used to provide information about the installed version of PostgreSQL, cannot be found on your system.
Fortunately, this error is usually easy to fix, and there are a few different methods you can use to resolve it. In this article, we will discuss some of the common causes of the “pg_config executable not found” error and walk you through some steps to fix it.
What is pg_config?
Before we get into the details of the error, let’s quickly discuss what pg_config is and what it does. Pg_config is a utility that comes with PostgreSQL, and it is used to provide information about the installation of PostgreSQL. This information includes things like the location of the PostgreSQL installation directory, the version of PostgreSQL that is installed, and the configuration options that were used when PostgreSQL was compiled.
Many libraries and extensions that are used with PostgreSQL require information from pg_config in order to compile correctly. For example, the popular Python library psycopg2, which is used to connect to PostgreSQL databases from Python, requires pg_config to be installed in order to build correctly.
Causes of the “pg_config executable not found” Error
The most common cause of the “pg_config executable not found” error is that PostgreSQL is not installed on your system, or it is installed in a location that is not in your system’s PATH environment variable. The PATH variable is used by your operating system to locate executables, so if the pg_config utility is not in a directory that is listed in your PATH variable, your system won’t be able to find it.
Another common cause of the error is that you are using an outdated version of PostgreSQL or the library or extension you are trying to install is not compatible with your version of PostgreSQL.
Finally, the error can also be caused by a permissions issue. If you do have PostgreSQL installed on your system, but you are logged in as a user that does not have permission to access the pg_config utility, you may see this error.
How to Fix the “pg_config executable not found” Error
There are several ways to fix the “pg_config executable not found” error, depending on the cause. Here are a few methods you can try:
1. Install PostgreSQL
If you don’t already have PostgreSQL installed on your system, the first step is to install it. You can download the latest version of PostgreSQL from the official website: https://www.postgresql.org/download/. Be sure to choose the version that is appropriate for your operating system.
2. Update your PATH variable
If you have PostgreSQL installed but your system cannot find the pg_config utility, you may need to update your PATH variable. To do this, you’ll need to add the directory that contains the pg_config utility to your system’s PATH variable.
The location of the pg_config utility varies depending on your operating system and how you installed PostgreSQL, but it is typically located in the bin directory of the PostgreSQL installation directory. For example, on a Linux system, the pg_config utility may be located at /usr/local/pgsql/bin/pg_config.
To add the directory to your PATH variable, you’ll need to open a terminal or command prompt and enter the following command (replacing the directory path with the actual path to the pg_config utility on your system):
On Windows, the command to update the PATH variable is slightly different:
3. Update or reinstall the library or extension
If you have updated PostgreSQL or installed it in a different location, you may need to update or reinstall the library or extension that is giving you the “pg_config executable not found” error. This is because the library or extension may have been compiled against a different version of PostgreSQL or may be looking for the pg_config utility in a different location.
To update or reinstall the library or extension, follow the installation instructions for that library or extension and make sure that the correct version of PostgreSQL is installed and that the pg_config utility can be found.
4. Check permissions
If you have PostgreSQL installed and the pg_config utility is in a directory that is listed in your PATH variable, but you are still getting the “pg_config executable not found” error, you may have a permissions issue. Make sure that the user account you are logged in as has permission to access the pg_config utility.
You can check the permissions on the pg_config utility by navigating to the directory that contains it and running the following command:
ls -l pg_config
This will display the permissions for the pg_config utility. Make sure that the user account you are logged in as has read and execute permissions on the file.
The “pg_config executable not found” error can be frustrating, but it is usually easy to fix. By following the steps outlined in this article, you should be able to resolve the error and get back to working with PostgreSQL and your favorite libraries and extensions. Remember to check that PostgreSQL is installed, update your PATH variable if necessary, and make sure that the correct version of PostgreSQL is installed and that the pg_config utility can be found.