Exercise about sql advanced basics

Advanced-sql.sql

mysql> SELECT team.name, COUNT(*) AS nb_student
    -> FROM team JOIN player ON team.id=player.team_id
    -> GROUP BY team_id
    -> ORDER BY nb_student DESC;
+------------+------------+
| name       | nb_student |
+------------+------------+
| Gryffindor |         36 |
| Slytherin  |         21 |
| Ravenclaw  |         15 |
| Hufflepuff |         12 |
+------------+------------+
4 rows in set (0,00 sec)

mysql> SELECT team.name
    -> FROM team JOIN player ON team.id=player.team_id
    -> GROUP BY team.name
    -> HAVING COUNT(*) >= 14
    -> ORDER BY team.name ASC;
+------------+
| name       |
+------------+
| Gryffindor |
| Ravenclaw  |
| Slytherin  |
+------------+
3 rows in set (0,00 sec)

mysql> SELECT team.name, wizard.firstname, wizard.lastname, enrollment_date
    -> FROM team JOIN player ON team.id=player.team_id
    -> JOIN wizard ON wizard.id=player.wizard_id
    -> WHERE team.id=1 AND DAYOFWEEK(enrollment_date) = 2
    -> ORDER BY enrollment_date ASC;
+------------+-----------+------------+-----------------+
| name       | firstname | lastname   | enrollment_date |
+------------+-----------+------------+-----------------+
| Gryffindor | George    | Weasley    | 1991-08-26      |
| Gryffindor | Alice     | Longbottom | 1992-02-17      |
| Gryffindor | Cadogan   |            | 1993-01-04      |
| Gryffindor | Godric    | Gryffindor | 1993-08-30      |
| Gryffindor | Sirius    | Black      | 1994-01-10      |
| Gryffindor | Aberforth | Dumbledore | 1995-04-24      |
| Gryffindor | Augusta   | Longbottom | 1999-10-25      |
+------------+-----------+------------+-----------------+
7 rows in set (0,01 sec)