How to determine if a date range occurs any time within another date range?

Question

I have an Event table that specifies a date range with start_date and end_date fields. I have another date range, specified in code, that defines the

Answer 1

You could write your condition like this:

start_date <= week_end AND end_date >= week_start

Edit: this assumes start_date <= end_date and week_start <= week_end ( are properly ordered) and gives you the best performance on most db implementations due to not using OR (which on some databases may create performance issues)

Edit2: this solution also solves the problem of events that begin before the interval and end after the interval.