如何避免在php mysql中插入相同的主键和值?

Please check my code below. When I insert values to the actor and movie table i get the different primary key but the the same values. I want to put all the same values into one primary key( expendables 3 should be in the primary key 19). Is this possible?By the way my primary key is auto_increment.See the picture below.Please check my code below. When I insert value