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

You'll need to write an insert trigger, and possible an update trigger if you want it to change when the record is changed. This article explains it quite nicely:

http://www.revsys.com/blog/2006/aug/04/automatically-updating-a-timestamp-column-in-postgresql/

CREATE OR REPLACE FUNCTION update_modified_column()   
RETURNS TRIGGER AS $$
BEGIN
    NEW.modified = now();
    RETURN NEW;   
END;
$$ language 'plpgsql';

Apply the trigger like this:

CREATE TRIGGER update_customer_modtime BEFORE UPDATE ON customer FOR EACH ROW EXECUTE PROCEDURE  update_modified_column();