Install aolserver4-nspostgres by entering the following commands in the terminal:
sudo apt update sudo apt install aolserver4-nspostgres
AOLserver 4 module: Postgres connector
This module implements a simple AOLserver database services driver for AOLserver version 4. . A database driver is a module which interfaces between the AOLserver database-independent nsdb module and the API of a particular DBMS. A database driver's job is to open connections, send SQL statements, and translate the results into the form used by nsdb. In this case, the driver is for the PostgreSQL ORDBMS from The PostgreSQL Global Development Group. . This is the official driver for the OpenACS project.