PostgreSQL upsert: do nothing if fields don't change

Question

Is it possible to express an upsert query, where nothing happens if the inserted data doesn't have any changes compared to what is already in the database?

Currently I have:

insert into feeds (link, title, category)
values (...)
on conflict (link)
do update set (title, category, _updated)
= (..., now()::timestamp)

Answer 1

You can add a where clause to the update part:

insert into feeds (link, title, category)
values (...)
on conflict (link)
do update 
   set (title, category, _updated) = (..., now()::timestamp)
where (feeds.title, feeds.category) is distinct from (excluded.title, excluded.category)