Knowing the count by using timeintervals

[#1]

Data:
LOAD
ID,EventID,EmpID,Timestamp#(Timings,'MM/DD/YYYY hh:mm TT') as Timings,
Date(floor(Timestamp#(Timings,'MM/DD/YYYY hh:mm TT'))) as Date
INLINE [
ID, EventID, EmpID, Timings
1, 0, 101, 8/9/2015 7:00 AM
2, 1, 101, 8/9/2015 11:30 AM
3, 0, 101, 8/9/2015 2:00 PM
4, 1, 101, 8/9/2015 5:45 PM
5, 0, 102, 8/9/2015 8:45 AM
6, 1, 102, 8/9/2015 11:45 AM
7, 0, 102, 8/9/2015 2:00 PM
8, 1, 102, 8/9/2015 5:30 PM
9, 0, 101, 8/16/2015 7:20 AM
10, 1, 101, 8/16/2015 2:20 PM
11, 0, 102, 8/16/2015 8:10 AM
12, 1, 102, 8/16/2015 11:45 AM
];

Interval:

load * inline [

IntervalSize

10 Minutes,

20 Minutes,

30 Minutes

1 Hour ]

here if i click on the 10 minutes i have to know how many employees are entering between 7-7:10,7:10-7:20 if we click on 20 minutes the intervals be 7-7:20,7:20-7:40  and how many employees are entering in these intervals and so on

how to get this requirement please help me

thanks in advanse