Re: SELECT Question - Mailing list pgsql-general

From Bruno Wolff III
Subject Re: SELECT Question
Date
Msg-id 20060303171501.GA15289@wolff.to
Whole thread Raw
In response to SELECT Question  (Alex <alex@meerkatsoft.com>)
List pgsql-general
On Sat, Mar 04, 2006 at 03:35:02 +1100,
  Alex <alex@meerkatsoft.com> wrote:
> Hi,
> i want to calculate the price difference, change% of 2 price records. Is
> there an easy way to do that within one query, rather than writing a
> function?

You can use a self join to do this. It won't be spectaculatly fast though.
The idea is too join each record to the record with the largest date less
than the date of the current record. Note that on record won't have a match.

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