posted 13 years ago
Whenever you buy the movie tickets there could be scenarios where you see multiple queues for the ticket window.It exactly works like a session in the database persistence world.If you have booked the seat first you will get that seat and to other person even if it was showing available when he initially started the booking has to leave that seat.It is one scenario when you have mutually exclusive access to the resources.
Apart from that lets say you work on one file from source code repository and you have made some changes to this.Same time other user have made some changes to the file and checked in the code before you submitted your changes to that file.Repository always ask you to either merge your changes or drop your changes to the same file whenever you try to submit your changes..These all are classic examples of multiple session used for accessing the same resources.Hope this helps