These type of questions are always difficult to answer because so many factors play a role in the outcome of a case. Is there a defense? Did the police arrest the defendant legally? Did the defendant confess? Does he have a prior record? What are the injuries alleged? Are they to an officer or with the use of a weapon (thats what makes it second degree)? Is he a prior felon? The legally correct answer is that there is no mandatory minimum jail time (he can get probation as long as he is not a felon) up to a maximum of 15 years. All of the above factors and more will determine where in between he falls. Many defendants don't do any time for a D felony assault case if they have no significant prior record and the injuries are not signficant. Others do upstate jail time.
DISCLAIMER- THIS CAN NOT AND DOES NOT TAKE THE PLACE OF LEGAL ADVICE> IT IS FOR INFORMATION PURPOSES ONLY. IT DOES NOT ESTABLISH AN ATTORNEY-CLIENT RELATIONSHIP. YOU SHOULD CONSULT A QUALIFIED LOCAL PRACTITIONER IN YOUR AREA FOR LEGAL ADVICE.
There is no standard sentence. Every case is different and sentences can vary greatly. The maximum sentence is 7 years and there is no minimum. That means you can get probation. You should speak to a lawyer as soon as possible and figure out if you have any defenses.