I have a datetime field in my MySql table where the date and time are recorded in the following format:
2010-12-17 18:06:59
I would like to select records where the datetime is in the last 15 minutes. How do I construct my query to do this?
I tried the following but it doesn't work:
// check in last 15 minutes
$time_duration = (15 * 60);
"SELECT COUNT(CounterId) AS Count FROM visitors_counter WHERE TimeStamp > NOW() - $time_duration"
Thanks!
You could just do the entire thing in MySQL:
SELECT COUNT(CounterId) AS Count
FROM visitors_counter
WHERE TimeStamp > (NOW() - INTERVAL 15 MINUTE)
You have to subtract an interval :
SELECT COUNT(*) AS Count
FROM visitors_counter
WHERE TimeStamp > NOW() - INTERVAL 15 MINUTE;
I replaced COUNT(CounterId) with COUNT(*) because the latter is faster if CounterId can't be null. If it can, just replace * with CounterId.
P.S. I don't consider timestamp a good column name because it's a key word. Sure, it works correctly, but it may be "better" to replace it with something else.
