Hi David, Thanks for your comments.
Okay, but you agree that there are DBAs and users who want to see the list of constraints, I think. My opinion is this doesn't exist because there isn't any demand for it.
I don't know if this is a good example, but if you look at StackOverflow, it seems that people who want to see a list of constraints appear regularly. (The other day, I also wanted to see the list, and I arrived at this site) Therefore, the only thing that hasn't been implemented so far is that no one could communicate the request to -hackers, and I think there is demand. https://stackoverflow.com/questions/62987794/how-to-list-all-constraints-of-a-table-in-postgresql Regards, Tatsuro Yamada