Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE track ( Track_ID int, Name text, Location text, Seating real, Year_Opened real )
TABLE: CREATE TABLE race ( Race_ID int, Name text, Class text, Date text, Track_ID text )

### Question ###
Display a pie chart for what are the different classes of races, and how many races correspond to each?

### Accurate SQL ###

SELECT Class, COUNT(*) FROM race GROUP BY Class