sql - MySQL COUNT query in join -
i have 2 tables.
the first table member table
member table id | name 1 | user 2 | user 3 | other user
and second table friends
friends table id | member_id | friend name | notified 1 | 1 | friend #1 | 0 2 | 1 | friend #1 | 1 3 | 2 | friend #1 | 0 4 | 1 | friend #1 | 1 5 | 2 | friend #1 | 1
what member table information total notified friends each member.
what have done until that
select m.id m.name count(f.notified) member m left join friends f on f.member_id = m.id f.notified = 1 group m.id
but this, not working me, because if have member not notified friends, query not included in results.
in above code example member id 3 not included in results.
any idea on how modify query in order return members no notified friends ?
kind regards merianos nikos
you can subquery in way :
select m.id, m.name, (select count(f.notified) friends f f.member_id = m.id , f.notified = 1) numfriends member m group m.id
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