Re: Help with CREATE FUNCTION - Mailing list pgsql-novice

On 18 April 2016 at 08:22, Kip Warner <kip@thevertigo.com> wrote:

Hey list,

I am having difficulty using CREATE FUNCTION with a subordinate SELECT
query that should operate on exactly two rows.

    http://pastebin.com/7b3Vxbuh

Any help is appreciated.

Your select should look like this:

select your_const*abs(ta.col1-tb.col1)+... 

from my_table as ta, my_table as tb where ta.id = arg_id_a and tb.id = arg_id_b;

This kind of unqualified join is usually stupid, but in this time exactly what you need.