Re: UPDATE ... SET = DEFAULT

Rod Taylor <rbt@rbt.ca> writes:
> It would seem a new primnode (change InsertDef into SetDefault or
> similar) will be required with some executor logic.

It is not the executor's business to know about defaults.  The rewriter
is the place where defaults get inserted - see rewriteTargetList().

Note that default NULL will have to be treated a little differently from
what we do for INSERT, since the, um, default behavior of UPDATE is to
preserve columns rather than replace 'em with nulls.
        regards, tom lane