Sum is incorrect when trying to join two tables

Question

I'm struggling with getting the correct sum from qty column when using joins. The problem occurs when I try to get the timestamp from the paymentType table and joining these against the rowid from orders and paymentType table and then grouping the timestamp on days (day(from_unixtime(paymentType.timestamp)))

I want the sum of qty by the hour using the timestamp in the paymentType table, the only link is the rowid (this is codeigniter's cart module's rowid ). The logical problem (at least for me) is that it exists more rows in the orders table (as this is per product) than the paymentType table (this is just to keep track of whether debit or cash was used). When I join these tables together, the sum for each hour gets multiplied by each hit in orders.rowid <--> paymentType.rowid .

I'm sorry if the explanation is bad, but I'm hoping that it's understandable enough that I could get help on this matter.

I have at least 10 queries I've tried, but none seem to work in the way I want.

The following is my orders table

+---------+----+-------+-----+----------+------------------+----------------------------------+
| orderID | id | price | qty | subtotal |       name       |              rowid               |
+---------+----+-------+-----+----------+------------------+----------------------------------+
|       3 | 49 |    35 |   1 |       35 | Red Bull Stor    | f457c545a9ded88f18ecee47145a72c0 |
|       4 | 24 |    35 |   1 |       35 | Monster Energy   | 1ff1de774005f8da13f42943881c655f |
|       5 | 49 |    35 |   1 |       35 | Red Bull Stor    | f457c545a9ded88f18ecee47145a72c0 |
|       6 | 19 |    20 |   1 |       20 | Sprite 0.5L      | 1f0e3dad99908345f7439f8ffabdffc4 |
|       7 |  1 |    25 |   1 |       25 | Pringles         | c4ca4238a0b923820dcc509a6f75849b |
|       8 | 43 |    20 |   1 |       20 | Lån av stekovn   | 17e62166fc8586dfa4d1bc0e1742c08b |
|       9 | 46 |    35 |   1 |       35 | Burn             | d9d4f495e875a2e075a1a4a6e1b9770f |
|      10 | 49 |    35 |   3 |      105 | Red Bull Stor    | f457c545a9ded88f18ecee47145a72c0 |
|      11 | 49 |    35 |   1 |       35 | Red Bull Stor    | f457c545a9ded88f18ecee47145a72c0 |
|      12 | 29 |    25 |   1 |       25 | Potetskruer      | 6ea9ab1baa0efb9e19094440c317e21b |
|      13 | 16 |    20 |   1 |       20 | Coca-Cola 0.5L   | c74d97b01eae257e44aa9d5bade97baf |
|      14 | 46 |    35 |   1 |       35 | Burn             | d9d4f495e875a2e075a1a4a6e1b9770f |
|      15 |  1 |    25 |   1 |       25 | Pringles         | c4ca4238a0b923820dcc509a6f75849b |
|      16 | 18 |    20 |   1 |       20 | Eventyrbrus 0.5L | 6f4922f45568161a8cdf4ad2299f6d23 |
|      17 | 16 |    20 |   1 |       20 | Coca-Cola 0.5L   | c74d97b01eae257e44aa9d5bade97baf |
|      18 | 15 |    30 |   1 |       30 | Coca-Cola 1.5L   | 9bf31c7ff062936a96d3c8bd1f8f2ff3 |
|      19 | 19 |    20 |   1 |       20 | Sprite 0.5L      | 1f0e3dad99908345f7439f8ffabdffc4 |
|      20 | 50 |    20 |   1 |       20 | Stratos bar      | c0c7c76d30bd3dcaefc96f40275bdc0a |
+---------+----+-------+-----+----------+------------------+----------------------------------+

This is the paymentType table

+-----------+-------------+------------+----------------------------------+
| paymentID | paymentType | timestamp  |              rowid               |
+-----------+-------------+------------+----------------------------------+
|         3 | Kort        | 1424447799 | f457c545a9ded88f18ecee47145a72c0 |
|         4 | Kort        | 1424448791 | 1ff1de774005f8da13f42943881c655f |
|         5 | Kort        | 1424452822 | f457c545a9ded88f18ecee47145a72c0 |
|         6 | Kort        | 1424454483 | c4ca4238a0b923820dcc509a6f75849b |
|         7 | Kort        | 1424454665 | d9d4f495e875a2e075a1a4a6e1b9770f |
|         8 | Kontant     | 1424454799 | f457c545a9ded88f18ecee47145a72c0 |
|         9 | Kontant     | 1424454825 | f457c545a9ded88f18ecee47145a72c0 |
|        10 | Kort        | 1424454870 | 6ea9ab1baa0efb9e19094440c317e21b |
|        11 | Kontant     | 1424455510 | d9d4f495e875a2e075a1a4a6e1b9770f |
|        12 | Kort        | 1424455847 | c4ca4238a0b923820dcc509a6f75849b |
|        13 | Kontant     | 1424456025 | 6f4922f45568161a8cdf4ad2299f6d23 |
|        14 | Kontant     | 1424456099 | c74d97b01eae257e44aa9d5bade97baf |
|        15 | Kontant     | 1424456148 | 9bf31c7ff062936a96d3c8bd1f8f2ff3 |
|        16 | Kontant     | 1424456242 | c0c7c76d30bd3dcaefc96f40275bdc0a |
|        17 | Kort        | 1424456266 | c74d97b01eae257e44aa9d5bade97baf |
|        18 | Kort        | 1424456445 | c0c7c76d30bd3dcaefc96f40275bdc0a |
|        19 | Kort        | 1424456964 | 70efdf2ec9b086079795c442636b55fb |
|        20 | Kort        | 1424457701 | 1ff1de774005f8da13f42943881c655f |
+-----------+-------------+------------+----------------------------------+

EDIT: SQL Queries I've tried so far, there exists more, but these are the latest. I would think these are the most "correct".

select orders.rowid, concat(convert(paymentType.timestamp,CHAR(11))) timestamp, orders.qty, orders.name
from orders
join paymentType
on orders.rowid = paymentType.rowid
order by paymentType.timestamp;

select orders.rowid, hour(from_unixtime(concat(convert(paymentType.timestamp,CHAR(11))))), orders.qty, orders.name
from orders
join paymentType
on orders.rowid = paymentType.rowid
#where orders.name = '".stripslashes($name)."'
order by paymentType.timestamp
;
select orders.qty, orders.name, orders.rowid, paymentType.rowid, paymentType.timestamp
from orders, paymentType
where orders.rowid = paymentType.rowid;

select qty, name, hour(from_unixtime(timestamp)) hour, day(from_unixtime(timestamp)) day
from orders_w_time
where name = 'Red Bull Stor'
;

select sum(qty) from orders
inner join (select distinct rowid from paymentType) pt
on orders.rowid = pt.rowid
where orders.name = 'Pølse';

select sum(orders.qty) totalqty, orders.name, pt.timestamp timestamp from orders ord
inner join (select timestamp from paymentType where paymentType.rowid = ord.rowid) pt
on orders.rowid = pt.rowid
where orders.name = 'Red Bull Stor';
select * from
(
select rowid, timestamp from paymentType
group by hour(from_unixtime(timestamp))
) pt
left join
(
select sum(qty), name, rowid from orders
) ord
on ord.rowid = pt.rowid
;
Select
  paymentType.rowid,
  orders.name,
  orders.qty,
  paymentType.timestamp
From
  orders,
  paymentType
Group By
  day(from_unixtime(paymentType.timestamp));

select sum(orders.qty) Total
from orders
left join
(
select rowid,timestamp
from paymentType
) as paymet on orders.rowid = paymet.rowid
group by day(from_unixtime(paymet.timestamp))
;

select paymentType.rowid, ord.qty, timestamp
from paymentType
left join
(
select orders.rowid, qty
from orders
) as ord on ord.rowid = paymentType.rowid
;

The intended result is to sum the qty column for 'Red Bull Stor' (ie.) for the each day grouped by the hour.

Answer 1

You can try something like this:

select o.name
     , pt.rowid
     , sum(o.qty)
     , hour(from_unixtime(pt.timestamp))
     , day(from_unixtime(pt.timestamp))
from orders o
join paymentType pt using(rowid)
where o.name = 'Red Bull Stor'
group by o.name
       , o.rowid
       , hour(from_unixtime(pt.timestamp))
       , day(from_unixtime(pt.timestamp));

SQLFiddle