Re: selecting random row

On tis, apr 02, 2002 at 06:57:21 +0000, Heiko Klein wrote:
> Hi,
>
> out of a table i.e. people:
> id last first sex age address
>
select id, random()
from people
order by 2
limit 1
;

The problem is that the entire table has to be sorted for each select. If it's
not very big, is suppose it's OK and better than your solution below.

> I would like to select a random id. Id's are a sequence, but some
> peoble have been deleted, so there are several id-holes in the
> table.
>
> Furthermore, I would like to specify the random person, like
>
> select 'random person id' from table where age > 60 and sex = 'm';
>
>
>
> Right now (in perl), I select the complete list of id's into a @list, do
> a $id = $list[rand(@list)] and have the right row. But this seems to be
> very time-consuming, and I would like to have it done completely in the
> Pg-database.
>
> Regards,
>
> Heiko
>
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