Re: selecting from cursor - Mailing list pgsql-hackers

From Tom Lane
Subject Re: selecting from cursor
Date
Msg-id 18108.994168944@sss.pgh.pa.us
Whole thread Raw
In response to Re: selecting from cursor  (Alex Pilosov <alex@pilosoft.com>)
Responses Re: selecting from cursor
List pgsql-hackers
Alex Pilosov <alex@pilosoft.com> writes:
>> And what are you doing with the places that don't care which kind of RTE
>> they are dealing with (which is most of them IIRC)?  While you haven't

> They just have things declared as RangeTblEntry *, and as long as they
> don't access type-specific fields, they are fine.

So you have four (soon to be six or seven) different structs that *must*
have the same fields?  I don't think that's cleaner than a union ...
at the very least, declare it as structs containing RangeTblEntry,
similar to the way the various Plan node types work (see plannodes.h).

> For scrollable cursors, Rescan should be implemented as 'scroll backwards
> until you can't scroll no more', correct?

No, it should be implemented as Rescan.  The portal mechanism needs to
expose the Rescan call for the contained querytree.
        regards, tom lane


pgsql-hackers by date:

Previous
From: Jan Wieck
Date:
Subject: Re: Trigger Procedures question
Next
From: Tom Lane
Date:
Subject: Re: AW: selecting from cursor