Re: get certain # of recs

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От Ian Barwick
Тема Re: get certain # of recs
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Msg-id 9nsmg6$1bip$1@news.tht.net
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Ответы Re: get certain # of recs
Список pgsql-general
Mike S. Nowostawsky wrote:

> How can one select only a certain number of records in Postgres?
>
> In other SQL langs we can use, say, for the first 20 recs:
>
> select  * from tablename where rownum < 21;
>
> WHAT should 'rownum' be to make this select work... OR is there a diff
> syntax?

use the LIMIT clause, e.g.

SELECT * FROM tablename LIMIT 20

for the first 20 rows, or

SELECT * FROM tablename LIMIT 10,20

for 10 rows beginning from the 20th row (or possibly the other way round,
the caffeine isn't working yet ;-)

When using LIMIT it is generally advisable to also use ORDER BY in order to
guarantee consistent result sets over repeated queries.

HTH

Ian Barwick


--
Ian Barwick - Developer
http://www.akademie.de

Remove SUNGLASSES to reply ;-)

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