"David G. Johnston" <david.g.johnston@gmail.com> writes:
> You've removed the "constraint verification scan" portion of this.
Indeed, because that's got nothing to do with adding a new column
(per se; adding a constraint along with the column is a different
can of worms).
> Re-reading this, the recommendation:
> - However, if the default value is volatile (e.g.,
> - <function>clock_timestamp()</function>)
> - each row will need to be updated with the value calculated at the time
> - <command>ALTER TABLE</command> is executed. To avoid a potentially
> - lengthy update operation, particularly if you intend to fill the
> column
> - with mostly nondefault values anyway, it may be preferable to add the
> - column with no default, insert the correct values using
> - <command>UPDATE</command>, and then add any desired default as
> described
> - below.
> has now been completely removed from the documentation.
Really? That's horrid, because that's directly useful advice.
regards, tom lane