I have two files A-nodes_to_delete and B-nodes_to_keep. Each file has a many lines with numeric ids. I want to have the list of numeric ids that are in nodes_to_delete but NOT in nodes_to_keep, i.e. A\B Doing it within a PostgreSQL database is unreasonably slow. Any neat way to do it in bash using Linux CLI tools? UPDATE: This would seem to be a Pythonic job, but the files are really, really large
![bash, Linux: Set difference between two text files](https://cdn-ak-scissors.b.st-hatena.com/image/square/98d6f053a97a87156775f60757c60865d0f2c47d/height=288;version=1;width=512/https%3A%2F%2Fcdn.sstatic.net%2FSites%2Fstackoverflow%2FImg%2Fapple-touch-icon%402.png%3Fv%3D73d79a89bded)