RA is a simple relational algebra interpreter. It has already been installed on your VM, and customized for this course to run on databases managed by the PostgreSQL server running on your VM. To run RA on a database named dbname, just issue the following command in your VM shell:
ra dbname

Once you are inside RA, refer to the public RA website for syntax of commands and relational algebra queries. You should ignore the beginning of that webpage about installing and running RA, since our setup is customized; start reading from the third paragraph under “Using RA” (“Once you are in RA, …“).

By default RA starts in an interactive mode, but you can run RA in a non-interactive mode instead, where it will read commands from an input file and write the result to an output file:
ra dbname inputfile.txt > outputfile.txt

IMPORTANT: Do NOT use internal options like -o and -i mentioned in the part of the public RA website that you should ignore.

To create/restore the example beers database in PostgreSQL (used as a running example on the RA homepage), run “/opt/dbcourse/examples/db-beers/setup.sh” from your VM shell.