date and time constraints

[monday89]

I have the following tables were subjects have overlapping date/time but i need to cut them by certain time to calculate different measures

have table. For example row 1 has a longer duration but row 2 has short. I need to assign row 2 start time as new stop time for row 1and create a row 3 that has row 1 as new stop dt but with row 2 stop dt time as new start time for row 3. It can have more than 2 observations. 

patient	start_time	stop_time	value1	value2
1	12/1/2019 0:00	12/1/19 22:12	1	4
1	12/1/2019 10:12	12/1/19 10:42	0.5	4

Want:

patient	start_time	stop_time	value1	value2
1	12/1/2019 0:00	12/1/2019 10:12	1	4
1	12/1/2019 10:12	12/1/19 10:42	0.5	4
1	12/1/19 10:42	12/1/19 22:12	1	4

I have no idea how to start to be honest, 

I tried _n = n + 1 for start_time < stop_date but i have no idea

[mkeintz]

do you expect any instances of more than 2 overlapping time-spans.  Or is it always exactly 2?  In other words, how far ahead do you need to look to determine all the needed start/stop pairs?

[monday89]

Thats a great question . it can be more than 2