Re: effective SELECT from child tables

Hannu Krosing <hannu(at)skype(dot)net> writes:

> I also often wish that this would be possible when someone adds a column
> with a default value to a multi-million row table on a 24/7 production
> system and insists on filling all existing columns with the default.
>
> A rule "ON SELECT FROM table_x WHERE col_x IS NULL return
> col_x=default_for_col_x" would solve that nicely.

Of course that only works if the reason they want to set fill the rows with
the default value isn't precisely because NULL is a perfectly reasonable thing
for the column to have (but not what they want for the existing rows).

--
greg