game表：
idmdatestadiumteam1team2 1001 8 June 2012 National Stadium, Warsaw POL GRE 1002 8 June 2012 Stadion Miejski (Wroclaw) RUS CZE 1003 12 June 2012 Stadion Miejski (Wroclaw) GRE CZE 1004 12 June 2012 National Stadium, Warsaw POL RUS ……
goal表：
matchidteamidplayergtime 1001 POL Robert Lewandowski 17 1001 GRE Dimitris Salpingidis 51 1002 RUS Alan Dzagoev 15 1002 RUS Roman Pavlyuchenko 82 ……
team表：
idteamnamecoach POL Poland Franciszek Smuda RUS Russia Dick Advocaat CZE Czech Republic Michal Bilek GRE Greece Fernando Santos ……
1、获取德国的比赛id和参赛人员。
The first example shows the goal scored by a player with the last name ‘Bender’. The * says to list all the columns in the table – a shorter way of saying matchid, teamid, player, gtime
Modify it to show the matchid and player name for all goals scored by Germany. To identify German players, check for: teamid = 'GER'
2、Show id, stadium, team1, team2 for just game 1012
From the previous query you can see that Lars Bender’s scored a goal in game 1012. Now we want to know what teams were playing in that match.
Notice in the that the column matchid in the goal table corresponds to the id column in the game table. We can look up information about game 1012 by finding that row in the game table.
Show id, stadium, team1, team2 for just game 1012
You can combine the two steps into a single query with a JOIN.
SELECT *
FROM game JOIN goal ON (id=matchid)
The FROM clause says to merge data from the goal table with that from the game table. The ON says how to figure out which rows in game go with which rows in goal – the matchid from goal must match id from game. (If we wanted to be more clear/specific we could say
ON (game.id=goal.matchid)
The code below shows the player (from the goal) and stadium name (from the game table) for every goal scored.
Modify it to show the player, teamid, stadium and mdate for every German goal.
4、Show the team1, team2 and player for every goal scored by a player called Mario player LIKE 'Mario%'
Use the same JOIN as in the previous question.
5、Show player , teamid , coach , gtime for all goals scored in the first 10 minutes gtime<=10< code><!--=10<-->
The table eteam gives details of every national team including the coach. You can JOIN goal to eteam using the phrase goal JOIN eteam on teamid=id
6、List the dates of the matches and the name of the team in which ‘Fernando Santos’ was the team1 coach.
To JOIN game with eteam you could use either
game JOIN eteam ON (team1=eteam.id) or game JOIN eteam ON (team2=eteam.id)
Notice that because id is a column name in both game and eteam you must specify eteam.id instead of just id
7、List the player for every goal scored in a game where the stadium was ‘National Stadium, Warsaw’
8、 The example query shows all goals scored in the Germany-Greece quarterfinal.
Instead show the name of all players who scored a goal against Germany.
HINT
Original: https://www.cnblogs.com/ruoli-121288/p/16278980.html
Author: 徐若离
Title: SQLZOO练习5–join（表的连接）
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