使用INNER JOIN将数字从一个表添加到另一个表 - 帮助！

Question

我在网上浏览并发现类似于我想要的东西，但它没有执行...请帮助

我的表格具有以下结构：

TABLE team
  id integer autoincrement primary key,
  name varchar,
  pointsfavor integer,
  pointscontra integer

TABLE game
  id integer autoincrement primary key,
  team1_id integer,
  team2_id integer,
  score1 integer, /*score for team1*/
  score2 integer /*score for team2*/

到目前为止，我有这个更新声明：

UPDATE team 
INNER JOIN game g1 ON (team.id = g1.team1_id)
INNER JOIN game g2 ON (team.id = g2.team2_id)
SET pointsfavor = pointsfavor 
      + IF(g1.score1 > g1.score2, g1.score1 - g1.score2, 0) 
      + IF(g2.score2 > g2.score1, g2.score2 - g2.score1, 0)
  , pointscontra = pointscontra 
      + IF(g1.score1 < g1.score2, g1.score2 - g1.score1, 0) 
      + IF(g2.score2 < g2.score1, g2.score1 - g2.score2, 0)
WHERE g1.id = 1;

当我把它放在我的sql中时它会执行该函数但它不会改变我的'pointsfavor'和'pointscontra'字段来自团队...所以它说，受影响的行（0）......

查找

以下是我在游戏表格中输入的值（得分1＆amp;得分2）：

这是我执行代码后的团队表...保持不变：

请帮助。

Answer 1

使用左连接而不是内连接：

UPDATE team 
LEFT JOIN game g1 ON (team.id = g1.team1_id)
LEFT JOIN game g2 ON (team.id = g2.team2_id)
SET pointsfavor = pointsfavor 
      + IF(g1.score1 > g1.score2, g1.score1 - g1.score2, 0) 
      + IF(g2.score2 > g2.score1, g2.score2 - g2.score1, 0)
  , pointscontra = pointscontra 
      + IF(g1.score1 < g1.score2, g1.score2 - g1.score1, 0) 
      + IF(g2.score2 < g2.score1, g2.score1 - g2.score2, 0)
WHERE g1.id = 1;

我不知道你的表字段是什么或你的代码是如何工作的，但我猜你的问题出在你的if语句中 例如，在第一次更新（pointsfavor）IF g1.score1＆gt; g1.score2然后g1.score1 - g1.score2和第二个if，但在第二次更新时g1.score1＆gt; g1.score2然后pointscontra + 0 + 0和下一个如果也做同样的事情 - 然后在这个查询中只是pointsfavor已经影响 因此，当第一个子句声明（pointsfavor）正确时，第二个子句的声明是不正确的！ 看看你的代码agian;）

Answer 2

两次更新（每个团队一次）：

UPDATE team t1
SET t1.pointsfavor = t1.pointsfavor + IF(game.score1 > game.score2, game.score1 - game.score2, 0)
, t1.pointscontra = t1.pointscontra + IF(game.score2 > game.score1, game.score2 - game.score1, 0)
FROM team
INNER JOIN game ON game.team1_id=t1.id
WHERE game.id = 1

UPDATE team t2
SET t2.pointsfavor = t2.pointsfavor + IF(game.score2 > game.score1, game.score2 - game.score1, 0)
, t2.pointscontra = t2.pointscontra + IF(game.score1 > game.score2, game.score1 - game.score2, 0)    
FROM team
INNER JOIN game ON game.team2_id=t2.id
WHERE game.id = 1