Re: OT - select + must have from - sql standard syntax?

Поиск
Список
Период
Сортировка
От Jim C. Nasby
Тема Re: OT - select + must have from - sql standard syntax?
Дата
Msg-id 20060613210246.GA34196@pervasive.com
обсуждение исходный текст
Ответ на OT - select + must have from - sql standard syntax?  (Antoine <melser.anton@gmail.com>)
Ответы Re: OT - select + must have from - sql standard syntax?  (Tom Lane <tgl@sss.pgh.pa.us>)
Список pgsql-performance
On Tue, Jun 13, 2006 at 02:43:45PM +0200, Antoine wrote:
> Hi,
> I don't have a copy of the standard on hand and a collegue is claiming
> that there must be a from clause in a select query (he is an oracle
> guy). This doesn't seem to be the case for postgres... does anyone
> know?

Dunno, but I know that other databases (at least DB2) don't require FROM
either. In Oracle, if you want to do something like

SELECT now();

you actually have to do

SELECT now() FROM dual;

where dual is a special, hard-coded table in Oracle that has only one
row. Personally, I find their approach to be pretty stupid.
--
Jim C. Nasby, Sr. Engineering Consultant      jnasby@pervasive.com
Pervasive Software      http://pervasive.com    work: 512-231-6117
vcard: http://jim.nasby.net/pervasive.vcf       cell: 512-569-9461

В списке pgsql-performance по дате отправления:

Предыдущее
От: "Shaun Thomas"
Дата:
Сообщение: Re: Confirmation of bad query plan generated by 7.4
Следующее
От: Tom Lane
Дата:
Сообщение: Re: Confirmation of bad query plan generated by 7.4 tree