Question

I have a data table that has the following columns: id (string), date (date), alert (0 or 1).

Some sample data:

case001     2011-06-18 8:27:00     0
case002     2011-06-18 16:30:00    1
case003     2011-06-19 7:24:00     0
...
case150     2011-10-23 22:05:00    1
case151     2011-10-24 11:45:00    1
case152     2011-10-24 16:55:00    0
case153     2011-10-24 20:13:00    0
...

I want to be able to write a few SQL queries to compute the number of alerts per day (where 1 represents an alert, 0 represents no alert) and also the number of alerts per id per day.

Any ideas?

Thank you!!!

Answer 1

It depends on which DB you are using.

In Oracle you can use trunc function to truncate to a day (or month, etc)

SELECT TRUNC(date, 'dd'), SUM(alert)
FROM alerts
GROUP BY TRUNC(date, 'dd')

In MySQL you should use

GROUP BY DATE(date)