pull up a chair

A friendly invitation to join a conversation, have a discussion or share a meal. A longer version of the same expression might be, "pull your chair up to the table and join us". A nice way of inviting someone to "have a seat".

Pull up a chair and join us.

Pull the Chair

A prank that you do on the bully at your school who is so mean you just wanna knock him out, but you don’t want to get suspense so you “pull the chair”.

Bully: You nerd!
Me... Pull the Chair

out under Sasha.

Me also: wools my bad.