Identify overlapping events in sharepoint calendar

first of all we need to identify set of events that we want to compare.

so we query a calendar list with some reasonable filtering condition. for this demonstration I haven't used any filters.

we need to query for event's start and end times, plus some event identifier, eg. ID or Title.

we save values for each queried fields to separate collection variable

to identify overlapping events, we need to compare them each to other.

so we will need two nested loops over collections returned from query above.

so we configure first for each loop over ID collection, and save current event's ID value and current index to a scalar variables

just like for first event we pick Start and End times for second event from source collection.

note the run-if condition at the beginning of loop, which prevents to compare each pair of events twice.

and proceed to comparison whether we have overlapping events or not.

so first set of conditions.

now we are sure whether events overlap or not.

if they do, we will save them to another collection variables.

we will maintain 6 of them - 3 variables for each of two events.

the same index position across all the 6 collections will identify data of two overlapping events

AND WE ARE DONE!

we have data of overlapping calendar events in collections and we can process them further as needed.

for this demo purposes we'll just write them to history log.