How do I automatically update a timestamp in PostgreSQL

Question

I want the code to be able to automatically update the time stamp when a new row is inserted as I can do in MySQL using CURRENT_TIMESTAMP.

How will I be able to achi

Answer 1

Updating timestamp, only if the values changed

Based on E.J's link and add a if statement from this link (https://stackoverflow.com/a/3084254/1526023)

CREATE OR REPLACE FUNCTION update_modified_column()
RETURNS TRIGGER AS $$
BEGIN
   IF row(NEW.*) IS DISTINCT FROM row(OLD.*) THEN
      NEW.modified = now(); 
      RETURN NEW;
   ELSE
      RETURN OLD;
   END IF;
END;
$$ language 'plpgsql';