Scott Ribe <scott_ribe@xxxxxxxxxxxxxxxx> writes: > I believe that if I UPDATE a row with the same values that it already has, this still dirties pages, writes the row, generates a WAL entry. There is no shortcut in the processing that's "hey, there's not really a change here, we'll just leave storage alone". > Is this correct? It is. We do offer a trigger you can add to suppress zero-change updates [1], but that's not the default behavior. We judged that checking for that would add more cycles than it removes, for most applications most of the time. regards, tom lane [1] https://www.postgresql.org/docs/current/functions-trigger.html
