SELECT all rows by WHERE clause - mysql

Question

I have the following query which works (without the "WHERE stats.dt" part). I get all users with their data.
My problem is that this query of course results in rows ONLY with users that have stats.dt > $timestampnow-$maxdays_data). But I need ALL users but their values of SUM(upload) or SUM(download) need only to be fetched when stats.dt is larger than tstamp-maxdays. The other rows with values of upload and download where stats.dt is smaller than what I need, can be ignored.
An example would be that the user with nodeid 2 would not be selected because his dt is too small. I do want the user to be selected but just not with data or upload values (they can be 0).
The stats table looks like this
nodeid | dt | upload | download
----------------------------------------
1 | 1381699533 | 345345 | 42324234
1 | 1382899152 | 7575 | 574234
1 | 1380699533 | 764534 | 7235232
2 | 1372899152 | 71455 | 124123
I don't know where to start looking how to solve this so maybe somebody out there can point me in the right direction. Thanks!
SELECT b.id, b.lastname, b.name, c.balance, a.maxdebt, b.warndata, b.warndownload, b.warnupload, b.warndebt, b.cutoffdata, b.cutoffdownload, b.cutoffupload, b.cutoffdebt, b.data, b.download, b.upload, b.warning, b.access, b.cutoffstop
FROM (
SELECT customers.id AS id, SUM(tariffs.value) AS maxdebt
FROM tariffs
LEFT JOIN assignments ON tariffs.id = assignments.tariffid
RIGHT JOIN customers ON assignments.customerid = customers.id
GROUP BY id
) a
JOIN (
SELECT customers.id AS id, UPPER(lastname) AS lastname, customers.name AS name, SUM(stats.upload+stats.download) AS data, SUM(stats.download) AS download, SUM(stats.upload) AS upload, customers.cutoffstop, warndata, warndownload, warnupload, warndebt, cutoffdata, cutoffdownload, cutoffupload, cutoffdebt, nodes.warning, nodes.access
FROM customers
LEFT JOIN nodes ON customers.id = nodes.ownerid
LEFT JOIN stats ON nodes.id = stats.nodeid
LEFT JOIN customerwarnings ON customers.id = customerwarnings.id
WHERE stats.dt > ($timestampnow-$maxdays_data)
GROUP BY id
) b ON a.id = b.id
JOIN (
SELECT customerid, SUM(cash.value) AS balance
FROM cash
GROUP BY customerid
) c ON b.id = c.customerid

Answer 1

Here's a brute force way of doing it. It can almost certainly be simplified, but without knowing more about the table and foreign key structures it's hard to be sure.
What I've done is replace sum(stats.download) with sum(case when stats.dt > ($timestampnow-$maxdays_data) then s.download end) and similarly for upload. I've also changed the join on b to be an outer join:
Select
b.id,
b.lastname,
b.name,
c.balance,
a.maxdebt,
b.warndata,
b.warndownload,
b.warnupload,
b.warndebt,
b.cutoffdata,
b.cutoffdownload,
b.cutoffupload,
b.cutoffdebt,
b.data,
b.download,
b.upload,
b.warning,
b.access,
b.cutoffstop
From (
Select
c.id,
sum(t.value) as maxdebt
From
tariffs t
left join
assignments a
on t.id = a.tariffid
right join
customers
on a.customerid = c.id
Group by
c.id
) a left outer join (
Select
c.id,
upper(lastname) as lastname,
c.name,
sum(s.upload + s.download) as data,
sum(case when stats.dt > ($timestampnow-$maxdays_data) then s.download end) as download,
sum(case when stats.dt > ($timestampnow-$maxdays_data) then s.upload end) as upload,
c.cutoffstop,
warndata,
warndownload,
warnupload,
warndebt,
cutoffdata,
cutoffdownload,
cutoffupload,
cutoffdebt,
n.warning,
n.access
From
customers c
left join
nodes n
on c.id = n.ownerid
left join
stats s
on n.id = s.nodeid
left join
customerwarnings w
on c.id = w.id
Group By
c.id
) b
On a.id = b.id
inner join (
Select
customerid,
sum(cash.value) as balance
From
cash
Group By
customerid
) c
on a.id = c.customerid