Mysql and case statement not working - mysql

Question

/*-------------temp table--------------*/
CREATE TEMPORARY TABLE IF NOT EXISTS bowlpick.tempschedule AS
(SELECT * FROM bowlpick.schedule
where season = (select max(year) from bowlpick.season));
/*-------------temp table--------------*/
set #g1= (select winner from bowlpick.tempschedule where game =1);
select date,name, #g1,bowl1 Pick,comf1
,case
when bowl1 = #g1 then comf1
when bowl1 <> #g1 then -comf1
else '0' end pts
from bowlpick.picks
where year(date) = (select max(year) from bowlpick.season)
order by bowl1 desc limit 5
<--------------------Table----------------->
name #g1 Pick comf1 pts
Player 1 Boise State Washington 7 -7
Player 2 Boise State Boise State 30 -30
Player 3 Boise State Boise State 21 -21
Player 4 Boise State Boise State 27 -27
Player 5 Boise State Boise State 15 -15
Why does this not work??? The last four pts should be positive numbers, not negative.
It as if the variable (#g1) is not working in the 'CASE' part. It works correctly when the 'select' part.
If I hard-code the winner (Boise State), it works correctly. Does variables not work in case statements?

Answer 1

Not sure why you are using temporary tables, you could do it in a single query, see the following example for somewhere to start, one other thing I noticed was that the case was returning numbers for the two case statements and a string for the else. Not only this the case statement has 2 WHEN statements which cover all bases surely meaning '0' would have never been selected anyway.
SELECT
bowlpick.picks.date
,bowlpick.picks.name
,bowlpick.tempschedule.winner
,bowlpick.picks.bowl1 Pick
,bowlpick.picks.comf1
,CASE
WHEN bowlpick.picks.bowl1 = bowlpick.tempschedule.winner THEN bowlpick.picks.comf1
WHEN bowlpick.picks.bowl1 <> bowlpick.tempschedule.winner THEN -bowlpick.picks.comf1
ELSE 0
END pts
FROM
bowlpick.picks
LEFT JOIN bowlpick.tempschedule ON year(bowlpick.picks.date) = bowlpick.tempschedule.season
WHERE
bowlpick.tempschedule.game =1
ORDER BY
bowl1 DESC
LIMIT 5
The following is an additional bit of work removing the need for the temporary table (links and grouping would need better defining but with an incomplete schema it's the best I could do)
SELECT
p.Date
,p.Name
,s.Winner
,p.Bowl1 Pick
,p.Comf1
,CASE
WHEN p.Bowl1 = s.Winner THEN p.Comf1
WHEN p.Bowl1 <> s.Winner THEN -p.Comf1
ELSE 0
END pts
FROM
picks p
LEFT JOIN schedule s ON YEAR(p.Date) = s.Season
WHERE
s.game = 1
GROUP BY
s.Season, p.Date
HAVING
s.Season = MAX(s.Season)
ORDER BY
p.Bowl1 DESC
LIMIT 5
He's my SQL Fiddle used to do this