Re: Table Sorting and Limit Question

Поиск
Список
Период
Сортировка
От Dawn Hollingsworth
Тема Re: Table Sorting and Limit Question
Дата
Msg-id 1028901334.1423.18.camel@kaos
обсуждение исходный текст
Ответ на Re: Table Sorting and Limit Question  (Ludwig Lim <lud_nowhere_man@yahoo.com>)
Ответы update on a large table  ("Aaron Held" <aaron@metrony.com>)
Список pgsql-sql
Since the id is a sequence type it should be unique. In this case it
also happens to be my primary key into this table which will also make
it unique. So the query below would only return 1 row. 

The part I'm missing is the offset number of the limit. Is there any way
to figure out which offset into the query would contain the id I'm
interested in.

Dawn Hollingsworth 
Principal Engineer 
AirDefense, Inc.


On Thu, 2002-08-08 at 21:42, Ludwig Lim wrote:
> 
> --- Dawn Hollingsworth <dmh@airdefense.net> wrote:
> > 
> > 
> > Currently we have a table with a sequence number( id
> > ) as a primary key,
> > a date field which is indexed and several other
> > columns. The user
> > interface allows the user to sort the data by date
> > and limits the result
> > set to 100 rows. 
> > 
> > The question is: 
> > The user interface needs the capability to sort the
> > table by date but
> > pull out the hundred row set that contains id
> > say...542 for example. 
> > 
> > What would be the best way to do this taking into
> > account this table is
> > several hundred thousand rows? 
> 
> try also to index the id.
> 
> Try :
> Select *
> from <table>
> where id=<id>
> order by date
> limit <limit no>
> 
> In this case you <limit no> is 100 since you want to
> return at most 100 rows.
> 
> hope that helps.
> 
> ludwig.
> 
> 
> __________________________________________________
> Do You Yahoo!?
> HotJobs - Search Thousands of New Jobs
> http://www.hotjobs.com
> 
> ---------------------------(end of broadcast)---------------------------
> TIP 1: subscribe and unsubscribe commands go to majordomo@postgresql.org




В списке pgsql-sql по дате отправления:

Предыдущее
От: Tom Lane
Дата:
Сообщение: Re: expressions operating on arrays
Следующее
От: Oleg Bartunov
Дата:
Сообщение: Re: expressions operating on arrays