Re: How to obtain algebraic sum of equal lines

On Tue, 25 Apr 2006 22:12:40 +0200
Ennio-Sr <nasr(dot)laili(at)tin(dot)it> wrote:

> Is it possible, given the following table:

> cod_rif | titolo | quantity | cmf | u_qq | mont | vend | sum
> ---------+--------+----------+---------+--------+---------+------+-------
> 26 | aaa | -1000 | 6.11098 | 6.176 | 6.1110 | t | -1000
> 7 | aaa | 2500 | 25.455 | 0 | 60.0897 | f | 2500
> 28 | bbb | 2700 | 3.862 | 4.6 | 4.1957 | f | 2700
[...]
> (10 rows)
> to get a selection whereby the algebraic sum of "quantity" for each equal 'titolo'
> is returned?

I am no expert but maybe you could try using "join":

SELECT t.*,s.sum AS quantity_sum FROM test_t AS t \


INNER JOIN (SELECT titolo,sum(quantity) FROM test_t GROUP BY titolo) AS s \
ON t.titolo = s.titolo ORDER BY t.titolo ASC

This (untested) command will just add a column quantity_sum to the result table.

Regards,

--
Oscar