Oracle update query to update records in sequential order

Question

I have a table in Oracle SQL whose ids are in increasing, sequential order, but there are gaps in the ids due to editing, e.g. the ids are currently something like

Answer 1

This solution to the same question you referenced shows how to do it:

update employee set emp_id = (
  with tab as (
    select emp_id, rownum r
    from   (select emp_id from employee order by emp_id)
  )
  select r from tab where employee.emp_id = tab.emp_id
);

That works. You cannot update a view that contains an analytic function like row_number - see Oracle 12C docs, look for "Notes on Updatable Views".