Aggregate Functions Oracle PLSQL

SQL> CREATE TABLE cars
  2  (
  3    MAKER  VARCHAR (25),
  4    MODEL  VARCHAR (25),
  5    PRICE  NUMERIC
  6  );
Table created.
SQL>
SQL> INSERT INTO CARS VALUES('CHRYSLER','CROSSFIRE',33620);
1 row created.
SQL> INSERT INTO CARS VALUES('CHRYSLER','300M',29185);
1 row created.
SQL> INSERT INTO CARS VALUES('HONDA','CIVIC',15610);
1 row created.
SQL> INSERT INTO CARS VALUES('HONDA','ACCORD',19300);
1 row created.
SQL>
SQL> INSERT INTO CARS VALUES('FORD','MUSTANG',15610);
1 row created.
SQL> INSERT INTO CARS VALUES('FORD','LATESTnGREATEST',NULL);
1 row created.
SQL> INSERT INTO CARS VALUES('FORD','FOCUS',13005);
1 row created.
SQL>
SQL>
SQL> SELECT
  2     Maker,
  3     COUNT(*)          total_count,
  4     COUNT(price)      car_prices
  5  FROM cars
  6  GROUP BY maker;
MAKER                     TOTAL_COUNT CAR_PRICES
------------------------- ----------- ----------
HONDA                            2.00       2.00
FORD                             3.00       2.00
CHRYSLER                         2.00       2.00
SQL>
SQL>
SQL>
SQL> drop table cars;
Table dropped.
SQL>