What is the name of the most expensive car?
name of the car refers to car_name; the most expensive refers to max(price)
SELECT T1.car_name FROM data AS T1 INNER JOIN price AS T2 ON T1.ID = T2.ID ORDER BY T2.price DESC LIMIT 1
database name:db_id cars
country table country Cols: origin dtype integer, country dtype text, 
price table price Cols: ID dtype integer, price dtype real, 
data table data Cols: ID dtype integer, mileage per gallon dtype real, number of cylinders dtype integer, displacement dtype real, horse power dtype integer, weight dtype integer, acceleration dtype real, model dtype integer, car name dtype text, 
production table production Cols: ID dtype integer, model year dtype integer, country dtype integer, 
