MySQL: filling empty fields with zeroes when using GROUP BY
- by SaltLake
I've got MySQL table
CREATE TABLE cms_webstat (
ID int NOT NULL auto_increment PRIMARY KEY,
TIMESTAMP_X timestamp DEFAULT CURRENT_TIMESTAMP,
# ... some other fields ...
)
which contains statistics about site visitors.
For getting visits per hour I use
SELECT
hour(TIMESTAMP_X) as HOUR
, count(*) AS HOUR_STAT
FROM cms_webstat
GROUP BY HOUR
ORDER BY HOUR DESC
which gives me
| HOUR | HOUR_STAT |
| 24 | 15 |
| 23 | 12 |
| 22 | 9 |
| 20 | 3 |
| 18 | 2 |
| 15 | 1 |
| 12 | 3 |
| 9 | 1 |
| 3 | 5 |
| 2 | 7 |
| 1 | 9 |
| 0 | 12 |
And I'd like to get following:
| HOUR | HOUR_STAT |
| 24 | 15 |
| 23 | 12 |
| 22 | 9 |
| 21 | 0 |
| 20 | 3 |
| 19 | 0 |
| 18 | 2 |
| 17 | 0 |
| 16 | 0 |
| 15 | 1 |
| 14 | 0 |
| 13 | 0 |
| 12 | 3 |
| 11 | 0 |
| 10 | 0 |
| 9 | 1 |
| 8 | 0 |
| 7 | 0 |
| 6 | 0 |
| 5 | 0 |
| 4 | 0 |
| 3 | 5 |
| 2 | 7 |
| 1 | 9 |
| 0 | 12 |
How should I modify the query to get such result?
Thanks.
