game表：

goal表:

eteam表

5.Show player, teamid, coach, gtime for all goals scored in the first 10 minutes gtime<=10

SELECT player, teamid,coach,gtime
  FROM goal JOIN eteam ON teamid=id 
 WHERE gtime<=10

6.List the the dates of the matches and the name of the team in which ‘Fernando Santos’ was the team1 coach.

SELECT mdate,teamname FROM game JOIN eteam ON 
    eteam.id=game.team1 AND coach='Fernando Santos'
 

7.List the player for every goal scored in a game where the stadium was ‘National Stadium, Warsaw’

SELECT player from game JOIN goal ON id=matchid AND stadium='National Stadium,Warsaw'

13.List every match with the goals scored by each team as shown. This will use “CASE WHEN” which has not been explained in any previous exercises.

Notice in the query given every goal is listed. If it was a team1 goal then a 1 appears in score1, otherwise there is a 0. You could SUM this column to get a count of the goals scored by team1. Sort your result by mdate, matchid, team1 and team2.

SELECT mdate,
    team1,SUM(CASE WHEN teamid=team1 THEN 1 ELSE 0 END) AS score1,
    team2,SUM(CASE WHEN teamid=team2 THEN 1 ELSE 0 END) AS score2
    FROM game LEFT JOIN goal ON id=matchid GROUP BY mdate,