Hard to tell for sure without seeing a picture, but it could be either a Black Ratsnake or a Coachwhip, neither of which is poisonous. But do not assume any snake is non-poisonous without a positive identification.
Northern Black Racer
I believe you are referring to the Grey Rat Snake.
Yellow teaser snake.look up broad banded Water Snake &Plain belly water snakes both are found in oklahoma & both are non-venomous.
There are several snakes that meet this description in the state of Oklahoma. Most likely it is a common garter snake or a Graham's crayfish snake. Both are known to swim and catch small fish.
black snake
A red racer snake is a slender snake with smooth shiny scales that are typically reddish-orange to light brown in color. They have a long, thin body and are known for their speed and agility. Their head is elongated and narrow, and they are non-venomous.
The black snake that has a pattern on it is the ring snake.
that's a northern ringneck snake
yes
The longest black snake in North America is named the black rat snake. The record size recorded of this black rat snake is eight feet in length. Which makes the black rat snake is the record longest.
That depends. The term black snake can apply to many different species of snake. The black rat snake, Pantherophis obsoletus, sometimes called the black snake, is indeed a rat snake.
No, the black rat snake is not poisonous.