CROSS JOIN of list of dates and another table - mysql

Question

I have a query for getting data from a certain table by date range and grouping by week. My CROSS JOIN intends to fill in a default value for each week where there are no results for the date range.
I can then execute this query.
SELECT
SUM(invoice.amount) AS "invoice.amount",
CONCAT(DATE_FORMAT(invoice.updated_at, '%b %d'), ' - ', DATE_FORMAT(DATE_ADD(invoice.updated_at, INTERVAL 7 DAY), '%b %d')) AS "invoice.updated_at"
FROM invoice
CROSS JOIN (
SELECT selected_date
FROM (
SELECT ADDDATE('1970-01-01',t4.i*10000 + t3.i*1000 + t2.i*100 + t1.i*10 + t0.i) selected_date
FROM
(SELECT 0 i union select 1 union select 2 union select 3 union select 4 union select 5 union select 6 union select 7 union select 8 union select 9) t0,
(SELECT 0 i union select 1 union select 2 union select 3 union select 4 union select 5 union select 6 union select 7 union select 8 union select 9) t1,
(SELECT 0 i union select 1 union select 2 union select 3 union select 4 union select 5 union select 6 union select 7 union select 8 union select 9) t2,
(SELECT 0 i union select 1 union select 2 union select 3 union select 4 union select 5 union select 6 union select 7 union select 8 union select 9) t3,
(SELECT 0 i union select 1 union select 2 union select 3 union select 4 union select 5 union select 6 union select 7 union select 8 union select 9) t4
) v
WHERE selected_date BETWEEN '2018-01-01' AND '2018-01-31'
GROUP BY selected_date, YEAR(selected_date), WEEK(selected_date)
) calendar
WHERE invoice.updated_at >= '2018-01-01'
AND invoice.updated_at <= '2018-01-31'
AND invoice.status = "PAID"
GROUP BY calendar.selected_date, invoice.id, invoice.amount, YEAR(invoice.updated_at), WEEK(invoice.updated_at)
Assume I have these records in the database:
+----+------------+------------+------------+
| id | amount | status | updated_at |
+----+------------+------------+------------+
| 1 | 1000 | PAID | 2018-01-01 |
| 2 | 2000 | PAID | 2018-01-01 |
| 3 | 100 | PAID | 2018-01-07 |
| 4 | 50 | PAID | 2018-01-11 |
+----+------------+------------+------------+
I expect to see these results, one record for every week of January:
+--------+-------------------+
| amount | updated_at |
+--------+-------------------+
| 3100 | Jan 1 - Jan 7 |
| 50 | Jan 8 - Jan 15 |
| 0 | Jan 16 - Jan 22 |
| 0 | Jan 23 - Jan 30 |
| 0 | Jan 31 - Jan 31 |
+--------+-------------------+
However, I get like 50 of these random duplicated results, the least of which contains the joined filler weeks since there are no 0 amounts:
+--------+----------------+
| amount | updated_at |
+--------+----------------+
| 1000 | Jan 1 - Jan 7 |
| 2000 | Jan 1 - Jan 7 |
| 100 | Jan 1 - Jan 7 |
| 50 | Jan 8 - Jan 15 |
| 1000 | Jan 1 - Jan 7 |
| 1000 | Jan 1 - Jan 7 |
| 2000 | Jan 1 - Jan 7 |
| 2000 | Jan 1 - Jan 7 |
| 100 | Jan 1 - Jan 7 |
| 50 | Jan 8 - Jan 15 |
| 100 | Jan 1 - Jan 7 |
| 50 | Jan 8 - Jan 15 |
| ... | ... |
| ... | ... |
| ... | ... |
+--------+----------------+
What gives?

Answer 1

GROUP BY calendar.selected_date, invoice.id, invoice.amount,
You have too many columns specified in the group by, particularly invoice.amount
Instead, try with:
GROUP BY
CONCAT(DATE_FORMAT(invoice.updated_at, '%b %d'), ' - ', DATE_FORMAT(DATE_ADD(invoice.updated_at, INTERVAL 7 DAY), '%b %d'))
I cannot be sure, but I think your date range needs adjustment as well, the following will guarantee you get everything for January 2018:
WHERE invoice.updated_at >= '2018-01-01'
AND invoice.updated_at < '2018-02-01'