Question

I have a simple MySql DB with some logdata.
I want get a forecast for events that repeats +-30min on a Weekday.
eg:
I compare 3 Events that match the criteria and give a alert.

And now the Question: What is the best method to compare the time?
I can put mktime or date() via PHP into the DB or I do it direct with mysql.

Answer 1

What could be done on database level most certainly should be done there, considering performance.

SELECT * FROM tbl WHERE mytime >= DATE_SUB(NOW(), INTERVAL 30 MINUTE)

This will search everything that is at most 30 minutes ago and newer. Feel free to modify this query to fit your needs.