How to schedule a job at a particular time and only if any changes are there?

I have created a job to run the build process daily with jenkins. It includes.
1. to checkin the code at a particular time.
2. to compile the code.
3. create and installer.
It is running in the scheduled time daily.
Is there any way to add one more step in the start to check whether any changes in the number of commits from the gitub repo and if no changes then skip the process.

The answer to the above requirement will be fulfilled with the below option in Poll SCM.

You need the give the schedule as below:

00 7 * * *

Which will initiate the build at 7 am in the morning as per system timezone and will check for any changes to the source as with previous build.If no changes then it will skip the build for that day.