Re: Why isn't DECLARE CURSOR ... FOR UPDATE supported?

On Thu, 2003-12-18 at 10:20, Tom Lane wrote:
> Is there any good reason for this restriction?
> 
> regression=# begin;
> BEGIN
> regression=# declare c cursor for select * from tenk1 for update;
> ERROR:  DECLARE CURSOR ... FOR UPDATE is not supported
> DETAIL:  Cursors must be READ ONLY.
> 
> While I have not tried it, I think that simply removing this error check
> in PerformCursorOpen() would allow the system to behave in a reasonable
> way, ie, locking each row the first time it is fetched through the
> cursor.

The help implies you can.

Command:     DECLARE
Description: define a cursor
Syntax:
DECLARE name [ BINARY ] [ INSENSITIVE ] [ [ NO ] SCROLL ]   CURSOR [ { WITH | WITHOUT } HOLD ] FOR query   [ FOR { READ
ONLY| UPDATE [ OF column [, ...] ] } ]