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* Join or Where?
@ 2003-06-26 11:21 Együd Csaba <csegyud@freemail.hu>
0 siblings, 1 reply; 2+ messages in thread
From: Együd Csaba @ 2003-06-26 11:21 UTC (permalink / raw)
To: pgsql-sql
Urgent Help : Use of return from function/procedure.Hi,
could anybody tell me what can be the difference between these queries?
There are a big difference but I can't understand the reasons. For some
reasons the firs query calculates getup column in a wrong way. It allways
devides with 10. (???) While the getupquantity column comes well.
With the second query everything is ok.
Thank you,
-- Csaba
----------------------------------------------------------------------------
-------
select (select getupquantity from t_products where id=productid) as
getupquantity,
quantity,
(select quantity/getupquantity) as getup
from t_stockchanges, t_products
where (getupquantity<>0)
limit 30;
RESULT:
getupquantity | quantity | getup
---------------+----------+-------
10 | 100 | 10
10 | 10600 | 1060
15 | 15150 | 1515
13 | 13650 | 1365
17.5 | 17500 | 1750
5.75 | 5750 | 575
2.5 | 2500 | 250
1.5 | 1500 | 150
16 | 16000 | 1600
2 | 2000 | 200
5.5 | 5500 | 550
4.5 | 4500 | 450
2 | 2000 | 200
----------------------------------------------------------------------------
-------
select t_products.getupquantity as getupquantity,
quantity,
(select t_stockchanges.quantity/t_products.getupquantity) as getup
from t_stockchanges
join t_products on (t_products.id=productid)
where (getupquantity<>0)
limit 30;
RESULT:
getupquantity | quantity | getup
---------------+----------+-------
10 | 100 | 10
10 | 10600 | 1060
15 | 15150 | 1010
13 | 13650 | 1050
17.5 | 17500 | 1000
5.75 | 5750 | 1000
2.5 | 2500 | 1000
1.5 | 1500 | 1000
16 | 16000 | 1000
2 | 2000 | 1000
5.5 | 5500 | 1000
4.5 | 4500 | 1000
2 | 2000 | 1000
--------------------------------------------------------------------
Hi,
could anybody tell me what can be the difference between these queries?
There are a big difference but I can't understand the reasons. For some
reasons the firs query calculates getup column in a wrong way. It allways
devides with 10. (???) While the getupquantity column comes well.
With the second query everything is ok.
Thank you,
-- Csaba
----------------------------------------------------------------------------
-------
select (select getupquantity from t_products where id=productid) as
getupquantity,
quantity,
(select quantity/getupquantity) as getup
from t_stockchanges, t_products
where (getupquantity<>0)
limit 30;
RESULT:
getupquantity | quantity | getup
---------------+----------+-------
10 | 100 | 10
10 | 10600 | 1060
15 | 15150 | 1515
13 | 13650 | 1365
17.5 | 17500 | 1750
5.75 | 5750 | 575
2.5 | 2500 | 250
1.5 | 1500 | 150
16 | 16000 | 1600
2 | 2000 | 200
5.5 | 5500 | 550
4.5 | 4500 | 450
2 | 2000 | 200
----------------------------------------------------------------------------
-------
select t_products.getupquantity as getupquantity,
quantity,
(select t_stockchanges.quantity/t_products.getupquantity) as getup
from t_stockchanges
join t_products on (t_products.id=productid)
where (getupquantity<>0)
limit 30;
RESULT:
getupquantity | quantity | getup
---------------+----------+-------
10 | 100 | 10
10 | 10600 | 1060
15 | 15150 | 1010
13 | 13650 | 1050
17.5 | 17500 | 1000
5.75 | 5750 | 1000
2.5 | 2500 | 1000
1.5 | 1500 | 1000
16 | 16000 | 1000
2 | 2000 | 1000
5.5 | 5500 | 1000
4.5 | 4500 | 1000
2 | 2000 | 1000
--------------------------------------------------------------------
^ permalink raw reply [nested|flat] 2+ messages in thread
* Re: Join or Where?
@ 2003-06-26 13:09 Richard Huxton <dev@archonet.com>
parent: Együd Csaba <csegyud@freemail.hu>
0 siblings, 0 replies; 2+ messages in thread
From: Richard Huxton @ 2003-06-26 13:09 UTC (permalink / raw)
To: Együd Csaba <csegyud@freemail.hu>; pgsql-sql
On Thursday 26 Jun 2003 12:21 pm, Együd Csaba wrote:
> Urgent Help : Use of return from function/procedure.Hi,
> could anybody tell me what can be the difference between these queries?
> There are a big difference but I can't understand the reasons. For some
> reasons the firs query calculates getup column in a wrong way. It allways
> devides with 10. (???) While the getupquantity column comes well.
>
> With the second query everything is ok.
1 > select (select getupquantity from t_products where id=productid) as
2 > getupquantity,
3 > quantity,
4 > (select quantity/getupquantity) as getup
5 > from t_stockchanges, t_products
6 > where (getupquantity<>0)
7 > limit 30;
I don't think the t_products in the first line is the same as that in the
fifth line - that'd surely mess up your values.
--
Richard Huxton
^ permalink raw reply [nested|flat] 2+ messages in thread
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2003-06-26 11:21 Join or Where? Együd Csaba <csegyud@freemail.hu>
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