Postgres does have notifications. And the article mentions this:
> Notifications are not part of the SQL standard and most relational databases do not support them. There are some exceptions, however. For example, PostgreSQL has very decent support for notifications.
I scanned the documentation TOC and found no mention of them. I guess I would have thought such a fundamental feature would show up in the TOC but it turns out you have to dig into the SQL documentation to find the NOTIFY and LISTEN statements.
If I had used the search feature on the word "notification" I would have found this but it's not necessarily obvious that they would actually be called that (ie. they could be called events or something else).
> Notifications are not part of the SQL standard and most relational databases do not support them. There are some exceptions, however. For example, PostgreSQL has very decent support for notifications.