Re: Selecting top N percent of records.

From: "Brent Wood" <b(dot)wood(at)niwa(dot)co(dot)nz>
To: <timuckun(at)gmail(dot)com>, <pgsql-general(at)postgresql(dot)org>
Subject: Re: Selecting top N percent of records.
Date: 2010-10-18 03:14:24
Message-ID: 4CBC72640200007B00030A45@gwia.niwa.co.nz
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Something like this should work - (but is untested), and does require the extra subquery, so there may be a more efficient way?

However, off the top of my head:

select a,b,c
from table
where
order by c desc
limit (select count(*)/10 from table where );

where c is the no of sales column

Brent Wood
DBA/GIS consultant
NIWA, Wellington
New Zealand
>>> Tim Uckun 10/18/10 3:40 PM >>>
Is there a way to select the top 10% of the values from a column?

For example the top 10% best selling items where number of sales is a column.

Thanks.

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