on 5/10/05 8:29 PM, Peter Brawley at peter.brawley@stripped wrote:
> Scott,
>
>> ...In part, my trouble is that I need to take the resuling zone from the
>> first
>> select and use that to determine the field name.
>
>> I can easily do this in my code in 2 selects, but was hoping to be able to
>> get the price back in just one select, if possible...
>
> If you have control over the data model, it would be good to change the
> structure of fedex_rates to (id int PK, zone int, weight int, price
> decimal(10,2)), getting rid of the denormalised z_* columns which are causing
> you problems. Then a one-stage query would just be SELECT price FROM
> fedex_rates WHERE zone=8 AND weight=12.
>
> If you're stuck with the table structure you show, you're stuck with two
> queries. If these lookup tables aren't large, there's probably not much
> performance to be gained from hiding the two stages inside a stored procedure,
> but if you want a one-step, IMO that's the way to go.
Ok, I changed the tables around a little, I can not really do this all in
one table, since the data gets made new often by fedex, at any rate, (no pun
intended :-))...
mysql> describe fedex_zones;
+-------+---------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+-------+---------+------+-----+---------+----------------+
| id | int(11) | | PRI | NULL | auto_increment |
| zip | char(5) | | UNI | | |
| zone | char(2) | | | | |
+-------+---------+------+-----+---------+----------------+
mysql> describe fedex_rates;
+--------+---------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+--------+---------------+------+-----+---------+----------------+
| id | int(11) | | PRI | NULL | auto_increment |
| weight | int(11) | | | 0 | |
| zone | int(11) | | | 0 | |
| price | decimal(10,2) | | | 0.00 | |
+--------+---------------+------+-----+---------+----------------+
so first, I need to get the zone I am in, which is a:
SELECT zone from fedex_zones where zip = 94947
> 8
If the result in that case is 8, then I can
select price from fedex_rates where zone = '8' and weight = '25'
For some reason, this join is still not screaming out at me, or maybe I have
it right, and my data is in duplication, any help is appreciated.
--
-------------------------------------------------------------
Scott Haneda Tel: 415.898.2602
<http://www.newgeo.com> Novato, CA U.S.A.
