Re: Fwd: What do these terms mean in the SOURCE CODE?

Thanks a lot for the answer. I see a lot of people discussing so many things
so I thought my email would have been ignored by those with a lot coming in
already. Thanks for the enlightenment.

-Vaibhav (*_*)

On Sun, Nov 21, 2010 at 12:25 AM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:

> On Fri, Nov 19, 2010 at 10:51 PM, Vaibhav Kaushal
> <vaibhavkaushal123(at)gmail(dot)com> wrote:
> > Is no one ready to help on this? :(
>
> Apparently, no one is ready to drop what they are doing to immediately
> answer your email before all the other ones they need to answer, but I
> wouldn't infer from that that no one wants to help. It doesn't seem
> very realistic to me to expect a 12-hour turnaround on free support,
> but what do I know?
>
> With regards to your question, for each type of plan node, there is an
> associated "plan state" node. This is an important distinction
> because, IIUC, plans can be reused, so plan state contains the
> information that might need to be reset on each run. Scan state is
> just a plan state node for a scan node. I believe a tuple projection
> is what you get when you do something like SELECT
> generate_series(1,10) FROM tbl - the set-returning function has to be
> "projected" in multiple tuples. EState I could use some hints on
> myself. A qual is a filter condition, e.g. in SELECT * FROM tbl WHERE
> x = 1, the "x = 1" part is a qual. It's helpful to grep src/include
> for the structures in question; the information they contain often
> helps to understand their purpose.
>
> --
> Robert Haas
> EnterpriseDB: http://www.enterprisedb.com
> The Enterprise PostgreSQL Company
>