Python Django filter avoid overlapping between range dates

Question

I'm having a bit of a logic blank this morning.

I get 2 datetime objects from a user (a range), start_time and end_time.

Idea is to return an exists if there's an overlap between the input range and an existing schedule time.

I tried the following, but I'm far off with the logic.

if Schedule.objects.filter(start_date__gte=ts_start, end_date__lte=ts_start).filter(start_date__gte=ts_end, end_date__lte=ts_end ).exists():

Answer 1

Two ranges [b₁, e₁] and [b₂, b_e] do not overlap if b₁>e₂, or e₁<b₂. We can negate this expression to know when two intervals overlap: b₁≤e₂, and e₁≥b₂.

This thus means that we can filter with:

Schedule.objects.filter(start_date__lte=ts_end, end_date__gte=ts_start)