selecting where in multiple join tables - mysql

Question

I have the logic worked out, just not sure how to best write this query.
the logic is
we have a deal ID of 1
a deal is linked to multiple regions
a deal is linked to multiple interests
a user is linked to multiple regions
a user is linked to multiple interests
we want all users where....
the user is linked to the same region as a deal
userRegionLink url, dealRegionLink drl
url.regionId is in drl.regionId where drl.dealId = 1
the user is linked to the same interest as a deal
userInterestLink uil, dealInterestLink dil
uil.interestId is in dil.interestId where dil.dealId = 1
this would give us a list of the users
now we need to select distinct from the list so we only end up sending each user a single email
But I have no idea what the best way to write this query would be.
We are dealing with a few tables here
We have
users which has all the user Information in it userId and other columns not important
userInterestLink which has userId and interestId
dealInterestLink which has dealId and interestId
userRegionLink which has userId and regionId
dealRegionLink which has dealId and regionId
so what we are wanting in the end is all the user info which matches.

Answer 1

I take RC's answer and modify it
SELECT u.userId, uil.interestId, url.regionId FROM users u
JOIN userInterestLink uil ON (uil.userId = u.userId)
JOIN userRegionLink url ON (url.userId = u.userId)
WHERE interestId IN (
SELECT DISTINCT interestId FROM dealInterestLink WHERE dealId = 1
) AND regionId IN (
SELECT DISTINCT regionId FROM dealRegionLink WHERE dealId = 1
)
as there is no need for LEFT JOIN if I exclude the NULL rows afterwards.
A more "symmetric" version without subqueries and with USING would be
SELECT u.userId, uil.interestId, url.regionId FROM users u
JOIN userInterestLink uil USING (userId)
JOIN userRegionLink url USING (userId)
JOIN dealInterestLink dil USING (interestId)
JOIN dealRegionLink drl USING (regionId, dealId)
WHERE dealId = 1
Untested as well.

Answer 2

Something like:
SELECT u.userId, uil.interestId, url.regionId FROM users u
LEFT JOIN userInterestLink uil ON (uil.userId = u.userId)
LEFT JOIN userRegionLink url ON (url.userId = u.userId)
WHERE uil.interestId IS NOT NULL AND uil.interestId IN (
SELECT DISTINCT interestId FROM dealInterestLink WHERE dealId = 1
) AND url.regionId IS NOT NULL AND url.regionId IN (
SELECT DISTINCT regionId FROM dealRegionLink WHERE dealId = 1
)
? If result is OK, you can then SELECT DISTINCT u.userId FROM users u -- ...
(not tested)

Answer 3

SELECT `u`.*
FROM `users` AS `u`
JOIN `userRegionLink` `userReg` USING ( `userId` )
JOIN `userInterestLink` `userInt` USING ( `userId` )
JOIN `dealInterestLink` `dealInt` USING ( `interestId` )
JOIN `dealRegionLink` `dealReg` USING ( `regionId` )
JOIN `deal` `d` ON ( `dealInt`.`dealId` && `dealReg`.`dealId` && `d`.`dealId` = 1 )
GROUP BY `u`.`userId`
Tested locally using dummy data and presumed schema. Worked OK.