Re: postgresql-8.0.jar and failure of ORDER BY parameters

Поиск
Список
Период
Сортировка
От Guillaume Cottenceau
Тема Re: postgresql-8.0.jar and failure of ORDER BY parameters
Дата
Msg-id 8764xz822q.fsf@meuh.mnc.ch
обсуждение исходный текст
Ответ на Re: postgresql-8.0.jar and failure of ORDER BY parameters  (Tom Lane <tgl@sss.pgh.pa.us>)
Список pgsql-jdbc
Tom Lane <tgl 'at' sss.pgh.pa.us> writes:

> Guillaume Cottenceau <gc@mnc.ch> writes:
> > I'd better write for example:
> >         actionSt.setString( 1, "surname" )
> > in order to sort by the value of the column named "surname", but
> > this has never "worked". Is it supposed to work now?
>
> No, that's just a different way of sorting by a constant.
>
> Parameters are *values*, they are not references to columns, and so
> there is no way to do what you want.  The fact that it happened to
> work like that before was an implementation artifact that has now
> gone away.

Ok.

> AFAICS you'll have to set up multiple prepared statements with all the
> different orderings you want.  This is not different from having to set
> up different statements depending on which columns you want displayed
> --- would you expect "SELECT ? FROM mytab" to allow run-time
> selection of a column?

True enough.

Thanks for the light.

--
Guillaume Cottenceau

В списке pgsql-jdbc по дате отправления:

Предыдущее
От: Tom Lane
Дата:
Сообщение: Re: postgresql-8.0.jar and failure of ORDER BY parameters
Следующее
От: Nahum Castro
Дата:
Сообщение: Re: Connectivity of postgreSQL database to a JSP page