Bonus Slides

        psql> SELECT * FROM autos;

         id | parent_id |      name      | audience_size | cpm  | is_actionable

        ----+-----------+----------------+---------------+------+---------------
          1 |           | General Motors |               |      | f
          2 |           | Toyota         |               |      | f
          3 |         1 | Chevrolet      |       1000000 | 0.80 | t
          4 |         1 | Cadillac       |        150000 | 1.00 | t
          5 |         2 | Corolla        |        800000 | 0.60 | t
          6 |         2 | Camry          |        600000 | 0.70 | t
          7 |         2 | Prius          |        400000 | 0.80 | t
          8 |         2 | RAV4           |        300000 | 0.50 | t
          9 |         3 | Spark          |        100000 | 0.15 | t
         10 |         3 | Sonic          |        150000 | 0.20 | t
         11 |         3 | Cruze          |        250000 | 0.20 | t
         12 |         3 | Malibu         |        200000 | 0.25 | t
         13 |         3 | Impala         |        175000 | 0.30 | t
         14 |         4 | Coupe          |        150000 | 0.30 | t
         15 |         4 | Sedan          |        150000 | 0.35 | t
         16 |         4 | Crossover      |        150000 | 0.40 | t
         17 |         4 | Escalade       |        150000 | 0.50 | t