My two tables are
Entry
event_id competitor_id place
101 101 1
101 102 2
101 201 3
101 301 4
102 201 2
103 201 3
second table lists prizes on offer for the events
Prize
event_id place money
101 1 120
101 2 60
101 3 30
102 1 10
102 2 5
102 3 2
103 1 100
103 2 60
103 3 40
From this I am looking to show all the information from the Entry table alongside the amount of money they won for their respected placing. If they failed to place in the money then a 0 will be displayed.
Any help would be appreciated.
try this:
SELECT a.Event_ID,
a.Competitor_ID,
a.Place,
COALESCE(b.money, 0) as `Money`
FROM entry a left join prize b
on (a.event_id = b.event_ID) AND
(a.place = b.Place)
hope this helps.
EVENT_ID COMPETITOR_ID PLACE MONEY
101 101 1 120
101 102 2 60
101 201 3 30
101 301 4 0 -- << this is what you're looking for
102 201 2 5
103 201 3 40
SELECT * FROM Entry NATURAL LEFT JOIN Prize;
If you absolutely want 0
instead of NULL
for the "money" when no prize was won (but how can you differentiate between a prize of 0 and no prize?):
SELECT Entry.*, COALESCE(money, 0) AS money FROM Entry NATURAL LEFT JOIN Prize;
See them both on sqlfiddle .
Try this:
select e.*, coalesce(p.money, 0) money from entry e
left join prize p
on e.event_id = p.event_id and e.place = p.place
You can play with the fiddle here .
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