mysql where condition priority
I have the following query and it gets the first result "Edit: of each contact" as I want but I do not need any other results per contact a开发者_如何转开发fter. So example if they have 3 phone # and one is main, it gives me the main then the other 2. I have tried grouping but it ends up getting the first one pulled no matter if main or not. Any thoughts to how I could do this without doing a php check in the loop for if contact already exists?
SELECT pc.firstname, pc.lastname, pp.areacode, pp.prefix, pp.last4
, if(pc.mainphone = pp.phoneid,1,0) as phone_priority
FROM contacts pc
JOIN phone pp ON ( (pp.contid = pc.contid && pp.phoneid = pc.mainphone) || (pp.contid = pc.contid) )
ORDER BY pc.lastname ASC, pc.firstname ASC, phone_priority DESC
Table setup:
contacts (id, firstname, lastname, mainphone) phone (id, areacode, prefix, last4)
Using MySQL 4.
Use a LIMIT expression to narrow the result set down to the first result. See SELECT Syntax for details.
Use LIMIT 1
at the end of your query
Use a left join:
SELECT pc.firstname,
pc.lastname,
pp.areacode,
pp.prefix,
pp.last4 ,
CASE
WHEN pp.mainphone IS NULL THEN 0
ELSE 1
END AS phone_priority
FROM contacts pc LEFT JOIN phone pp
ON pp.contid = pc.contid
AND pp.phoneid = pc.mainphone
ORDER BY pc.lastname ASC, pc.firstname ASC, phone_priority DESC
Try this variant -
SELECT t.contid
, t.firstname
, t.lastname
, if(t.phoneid IS NULL, p2.phoneid, t.phoneid) phone
, if(t.phoneid IS NULL, p2.areacode, t.areacode) areacode
, if(t.phoneid IS NULL, p2.prefix, t.prefix) prefix
, if(t.phoneid IS NULL, p2.last4, t.last4) last4
FROM
(
SELECT c.contid
, c.firstname
, c.lastname
, c.mainphone
, p.phoneid
, p.areacode
, p.prefix
, p.last4
FROM
contacts c
LEFT JOIN phone p
ON c.contid = p.contid AND c.mainphone = p.phoneid) t
LEFT JOIN phone p2
ON t.contid = p2.contid AND t.mainphone <> p2.phoneid
GROUP BY
t.contid
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