Re: select count(*) and limit

Поиск
Список
Период
Сортировка
От Verena Ruff
Тема Re: select count(*) and limit
Дата
Msg-id 446C969E.60109@triosolutions.at
обсуждение исходный текст
Ответ на Re: select count(*) and limit  (Oscar Rodriguez Fonseca <info@vraniscci.com>)
Список pgsql-novice
Oscar Rodriguez Fonseca schrieb:
> TABLE IN DB:
>
>
> number_times | user_name   | last_login
> ----------------------------------------
>  1           | Paul        | 11-12-2005
>  4           | Mary        | 08-11-2005
>  5           | Charles     | 01-02-2005
>
> [...]
>
> SELECT count(*) AS number_times,NULL AS user_name,NULL as last_login \
> FROM table UNION ALL SELECT * FROM table LIMIT 2;
>
> This has the practical drawback that you need an integer column in your
> table to get the query working as expected and the design drawback that
> it is a little bit weird and somewhat non-standard way of querying.
>
I think this is a little bit to weired. It should be possible for
another person what I am doing without explaing such a lot.

> BTW, I had a similar problem and solved it storing the full result list
> in a temporal variable on the server but "session-wise" (when the user
> opens another unrelated page, the application frees the variable). This
> is possible in my case because my app won't have more than 10 clients
> at once and therefore it don't represent much memory overhead
This is possible if there are only little users and only a few hundred
records. I have only few users, too, but some tenthousonds records and I
don't think it would be a good idea storing them completly in the
servers memory.

Regards,
Verena

В списке pgsql-novice по дате отправления:

Предыдущее
От: Oscar Rodriguez Fonseca
Дата:
Сообщение: Re: select count(*) and limit
Следующее
От: Verena Ruff
Дата:
Сообщение: Re: select count(*) and limit