I am running a batch job but it gets stuck in middle and not moving further. Has anyone faced similar thing before?
Batches can be stuck and give no indication of a failure if there is a fault with the data that salesforce has not handled. For example, this can happen with objects like opportunity and opportunity line item, for sandbox refreshed from production during high user activity period. It might be worth raising a case with salesforce if this is happening quite often so that they can look into their logs and come back to you with details. This process would take a couple of days