Group By not aggregating the group by column in SQL

Question

I'm trying to get a count of users who have paid for a service and signed up in a certain year from a mysql db. A member can pay for multiple services so can be counted twice:

select 
    count(payment_order.memberId) as members,
    from_unixtime(account_login.memberFrom, '%Y') as memberFrom
from 
    payment_order
join 
    account_login 
on 
    payment_order.memberId = account_login.memberId
Where 
    account_login.memberFrom != '0'
    and payment_order.`status` = 'paid'
    and payment_order.dateCompleted >= '2010-01-01 00:00:00'
    and payment_order.dateCompleted <= '2011-12-31 23:59:59'
group by memberFrom

Rather than grouping by years, it seems to be grouping by the individual member count. I think I'm doing something and can;t see the wood for the trees:

1, 2005
4, 2005
1, 2005
1, 2006
5, 2006
5, 2006

What I'm looking for is

 6, 2005
11, 2006

Grateful for any pointers that may explain my befuddlement

Answer 1

You're grouping by account_login.memberFrom , which creates each individual row.

Then you're selecting from_unixtime(account_login.memberFrom, '%Y') on each of those rows, creating the duplicate values.

Instead, use GROUP BY from_unixtime(account_login.memberFrom, '%Y')