Re: SQL CASE Statements

Halley, here is a sample for you that might help; the purpose of this
function was to set an indicator of '1' or '0' (true or false) on a router
interface if the router interface ID was the same as the default gateway for
the Router node ID:

create view current_default_gateways_v (router_id, default_gateway) AS
select router_id,
case
when router_id in (select interface_id from router_interface ri,
network_nodes nn
where ri.node_id = nn.node_id
and ri.interface_id = nn.default_gateway_interface_id)
then 1
else 0
end as if_default_gateway
from router_interface;

TABLES USED:
network_nodes:
node_id, serial
node_name, varchar
default_gateway_interface_id, integer

router_interfaces:
interface_id, serial (integer)
node_id (FK)

-----Original Message-----
From: Halley Pacheco de Oliveira [mailto:halleypo(at)yahoo(dot)com(dot)br]
Sent: Saturday, August 20, 2005 7:25 AM
To: pgsql-sql(at)postgresql(dot)org
Cc: lvaningen(at)esncc(dot)com
Subject: RE: SQL CASE Statements

> Has anybody done this? If so, can you send me a sample?

CREATE TEMPORARY TABLE fruits (id SERIAL, name TEXT);
INSERT INTO fruits VALUES (DEFAULT, 'banana');
INSERT INTO fruits VALUES (DEFAULT, 'apple');
CREATE TEMPORARY TABLE food (id SERIAL, name TEXT);
INSERT INTO food VALUES (DEFAULT, 'apple');
INSERT INTO food VALUES (DEFAULT, 'spinach');
SELECT name, CASE WHEN name = ANY (SELECT name FROM fruits)
THEN 'yes'
ELSE 'no'
END AS fruit
FROM food;

name | fruit
---------+-------
apple | yes
spinach | no
(2 lines)

__________________________________________________
Converse com seus amigos em tempo real com o Yahoo! Messenger
http://br.download.yahoo.com/messenger/