Oracle Trigger Updating a field on an Insert or an Update -

For some reason I am running an empty about doing something like this.

I have a table that looks like this:

  UserID | Name | Date added | Last update ------------------------------------------------ - - 1 | James Q | 1/1/2009 |  

If I include or update the last updated field, then it should update sysdate. How will I go about doing something like this?

  Add or trigger your_trigger_name before or trigger on your_table for each line Start : New.LastUpdated: = sysdate; End;  

Try it was not an Oracle server in my hand, but I hope I got the right to syntax.