Re: get first and last row in one sql as two columns - Mailing list pgsql-general

From Dickson S. Guedes
Subject Re: get first and last row in one sql as two columns
Date
Msg-id 20150903105106.GB6274@dba01
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In response to get first and last row in one sql as two columns  (Tom Smith <tomsmith1989sk@gmail.com>)
Responses Re: get first and last row in one sql as two columns
List pgsql-general
On Wed, Sep 02, 2015 at 07:14:40PM -0400, Tom Smith wrote:
> Hi:
>
> I need to get the first and last tow in one sql like below
>
> select first(col1), last(col1) from table order by col1

Have you tried the window functions [1] last_value and first_value?

You could use something like:

SELECT first_value(col1) over (order by col1),
       last_value(col1)  over (order by col1)
FROM table;

It should be as simple as that, or I miss your point.


[1] http://www.postgresql.org/docs/current/static/functions-window.html


[]s
--
Dickson S. Guedes
@guediz - http://github.com/guedes

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