How to get the count() for each day

Question

Im working with analytics and I would like to get the count for each day and also it will return 0 for the day with no count. Im using MYSQL.

This is my query:

SELECT DAY(a.Date)
FROM (
    SELECT LAST_DAY(CURDATE()) - INTERVAL (a.a + (10 * b.a) + (100 * c.a)) DAY AS DATE
    FROM (SELECT 0 AS a UNION ALL SELECT 1 UNION ALL SELECT 2 UNION ALL SELECT 3 UNION ALL SELECT 4 UNION ALL SELECT 5 UNION ALL SELECT 6 UNION ALL SELECT 7 UNION ALL SELECT 8 UNION ALL SELECT 9) AS a
    CROSS JOIN (SELECT 0 AS a UNION ALL SELECT 1 UNION ALL SELECT 2 UNION ALL SELECT 3 UNION ALL SELECT 4 UNION ALL SELECT 5 UNION ALL SELECT 6 UNION ALL SELECT 7 UNION ALL SELECT 8 UNION ALL SELECT 9) AS b
    CROSS JOIN (SELECT 0 AS a UNION ALL SELECT 1 UNION ALL SELECT 2 UNION ALL SELECT 3 UNION ALL SELECT 4 UNION ALL SELECT 5 UNION ALL SELECT 6 UNION ALL SELECT 7 UNION ALL SELECT 8 UNION ALL SELECT 9) AS c
) a
WHERE a.Date BETWEEN (CURDATE() - INTERVAL 31 DAY) AND CURDATE() GROUP BY a.Date;

I got the query for getting the days for 31 day but i can't get the count() for each day.

Example:

I have a shipment table with the following columns:

id = some id

status = 'Dispatched', 'Delivered', 'Completed'

date_dispatched = some date

I want to count all data with dispatched status for 31 days.

Example of expected output:

+-----+--------+
| Day | Count  |
+-----+--------+
| 25  |   0    |
| 26  |   0    |
| 27  |   0    |
| 28  |   0    |
| 29  |   12   |
| 30  |   24   |
| 31  |   34   |
| 1   |   24   |
| 2   |   67   |
| 3   |   0    |
| 4   |   0    |
| 5   |   0    |
| 6   |   0    |
| 7   |   0    |
| 8   |   0    |
| 9   |   0    |
| 10  |   0    |
| 11  |   12   |
| 12  |   44   |
| 13  |   67   |
| 14  |   0    |
| 15  |   0    |
| 16  |   0    |
| 17  |   0    |
| 18  |   0    |
| 19  |   0    |
| 20  |   0    |
| 21  |   0    |
| 22  |   0    |
| 23  |   0    |
| 24  |   0    |
+--------------+

Answer 1

This example from 2015-01-01 to 2015-01-31

select lstOfDays, date_dispatched,case when Dispatched_Count is null then 0 else Dispatched_Count end as Dispatched_Count from
(SELECT ADDDATE('2015-01-01', INTERVAL @i:=@i+1 DAY) AS lstOfDays
        FROM (
        SELECT a.a
        FROM (SELECT 0 AS a UNION ALL SELECT 1 UNION ALL SELECT 2 UNION ALL SELECT 3 UNION ALL SELECT 4 UNION ALL SELECT 5 UNION ALL SELECT 6 UNION ALL SELECT 7 UNION ALL SELECT 8 UNION ALL SELECT 9) AS a
        CROSS JOIN (SELECT 0 AS a UNION ALL SELECT 1 UNION ALL SELECT 2 UNION ALL SELECT 3 UNION ALL SELECT 4 UNION ALL SELECT 5 UNION ALL SELECT 6 UNION ALL SELECT 7 UNION ALL SELECT 8 UNION ALL SELECT 9) AS b
        CROSS JOIN (SELECT 0 AS a UNION ALL SELECT 1 UNION ALL SELECT 2 UNION ALL SELECT 3 UNION ALL SELECT 4 UNION ALL SELECT 5 UNION ALL SELECT 6 UNION ALL SELECT 7 UNION ALL SELECT 8 UNION ALL SELECT 9) AS c
        ) a
        JOIN (SELECT @i := -1) r1
        WHERE 
        @i < DATEDIFF('2015-01-31', '2015-01-01')) as a

LEFT JOIN

(select date_dispatched, Status, count(1) as Dispatched_Count from
 shipment_table where Status =  'Dispatched'  GROUP BY date_dispatched) as b

on a.lstOfDays = b.date_dispatched ORDER BY lstofDays

You have to input StartDate and EndDate

This will return an output something like:

lstofDays   date_dispatched   Dispatched_Count

2015-01-01                           0
2015-01-02                           0
2015-01-03                           0
2015-01-04                           0
2015-01-05                           0
2015-01-06                           0
2015-01-07    2015-01-07             1
2015-01-08                           0
2015-01-09    2015-01-09             2
2015-01-10                           0
2015-01-11                           0
2015-01-12                           0
2015-01-13                           0
2015-01-14                           0
2015-01-15                           0
2015-01-16                           0
2015-01-17                           0
2015-01-18                           0
2015-01-19                           0
2015-01-20                           0
2015-01-21                           0
2015-01-22                           0
2015-01-23                           0
2015-01-24                           0
2015-01-25                           0
2015-01-26                           0
2015-01-27                           0
2015-01-28                           0
2015-01-29                           0
2015-01-30                           0
2015-01-31                           0

You need to add the year and month otherwise it will include all of your date_dispatched fields.

Or this will generate automatically from Date Today - 31 days

set @edate = DATE_FORMAT(CURDATE(), "%Y-%m-%d");
set @sdate = DATE_ADD(DATE_FORMAT(CURDATE(), "%Y-%m-%d"),INTERVAL -31 DAY);

select case when date_dispatched is null then Date_format(date(lstOfDays),'%d') else Date_format(date(date_dispatched),'%d') end date_dispatched,
case when Dispatched_Count is null then 0 else Dispatched_Count end as Dispatched_Count from
(SELECT ADDDATE(@sdate, INTERVAL @i:=@i+1 DAY) AS lstOfDays
        FROM (
        SELECT a.a
        FROM (SELECT 0 AS a UNION ALL SELECT 1 UNION ALL SELECT 2 UNION ALL SELECT 3 UNION ALL SELECT 4 UNION ALL SELECT 5 UNION ALL SELECT 6 UNION ALL SELECT 7 UNION ALL SELECT 8 UNION ALL SELECT 9) AS a
        CROSS JOIN (SELECT 0 AS a UNION ALL SELECT 1 UNION ALL SELECT 2 UNION ALL SELECT 3 UNION ALL SELECT 4 UNION ALL SELECT 5 UNION ALL SELECT 6 UNION ALL SELECT 7 UNION ALL SELECT 8 UNION ALL SELECT 9) AS b
        CROSS JOIN (SELECT 0 AS a UNION ALL SELECT 1 UNION ALL SELECT 2 UNION ALL SELECT 3 UNION ALL SELECT 4 UNION ALL SELECT 5 UNION ALL SELECT 6 UNION ALL SELECT 7 UNION ALL SELECT 8 UNION ALL SELECT 9) AS c
        ) a
        JOIN (SELECT @i := -1) r1
        WHERE 
        @i < DATEDIFF(@edate,@sdate)) as a

LEFT JOIN

(select date_dispatched, Status, count(1) as Dispatched_Count from
shipment_table where Status =  'Dispatched'  GROUP BY date_dispatched) as b

on a.lstOfDays = b.date_dispatched ORDER BY lstofDays

result:

26  0
27  0
28  0
29  0
30  0
31  0
01  0
02  0
03  0
04  0
05  0
06  0
07  0
08  0
09  0
10  0
11  0
12  0
13  0
14  0
15  0
16  0
17  1
18  0
19  2
20  0
21  0
22  0
23  0
24  0
25  0
26  0

Answer 2

TRY THIS: You should GROUP BY days and count the value based on condition as below:

SELECT DAY(date_dispatched) Days,
    COUNT(1) AS DispatchedCount 
--Place the column here if you have any particular like `dispatched_number`
--If we have separate rows for every transaction then `COUNT(1) will work fine`
FROM shipment
WHERE status = 'Dispatched'
    AND date_dispatched BETWEEN DATE_SUB(CURDATE(), INTERVAL 30 DAY) AND CURDATE()
GROUP BY DAY(date_dispatched)
ORDER by DAY(date_dispatched);

You can see the count of each status so you need to remove status = 'Dispatched' from where and use below CASE in the select

SUM(CASE WHEN status = 'Dispatched' THEN 1 ELSE 0 END) AS DispatchedCount,
SUM(CASE WHEN status = 'Delivered' THEN 1 ELSE 0 END) AS DeliveredCount,
SUM(CASE WHEN status = 'Completed' THEN 1 ELSE 0 END) AS CompletedCount,