database
https://en.wikipedia.org/wiki/Database
https://www.youtube.com/watch?v=MqbVoSs0lXk (What Is a Database?)
PostgreSQL
https://en.wikipedia.org/wiki/PostgreSQL
https://www.youtube.com/watch?v=VEWXmdjzIpQ (Wait... PostgreSQL can do WHAT?)
https://github.com/vivus-ignis/the-art-of-the-terminal/tree/master/postgresql-is-not-a-database
https://www.postgresql.org/docs/current/xplang.html
https://wiki.postgresql.org/wiki/PL_Matrix
https://github.com/tembo-io/trunk
https://pgt.dev/extensions/pg_cron
https://pgt.dev/extensions/hstore
https://pgt.dev/extensions/pgmq
https://tembo.io/pricing/
https://github.com/tembo-io/tembo
SQLite
https://en.wikipedia.org/wiki/SQLite