Re: Prepare/Declare

On Thu, May 24, 2007 at 04:07:27PM -0400, Tom Lane wrote:
> Michael Meskes <meskes@postgresql.org> writes:
> > PREPARE p AS
> >     SELECT * FROM foo;
> > DECLARE c CURSOR for p;
> 
> > AFAIRC the standard says this group of statements are perfectly legal
> 
> I'd be interested to see where you draw that conclusion, since
> (a) PREPARE statements of that form are not in the standard, and
> (b) DECLARE CURSOR is clearly defined as taking a <query expression>.

Sorry, should have been more precise. I was talking about embedded SQL
standard. Just look for "dynamic cursors".

> You can achieve something approximating this at the protocol level,
> since you can do partial fetches from a portal created by Bind'ing
> the prepared statement.  That won't let you fetch backwards nor
> persist the cursor past end of transaction, but maybe you don't
> need those things.

I could also keep my old simultaing code for this special case, which is
probably the best way to do it.

Michael
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