从一个表字段添加数字到另一个表字段？

Question

我想知道如何将一个表字段中的数字添加到另一个表字段中，例如，我有：

Table name = Game: 

opponent1(name of row) vs. opponent 2    -  score1 = 25 - score2 =  20

我希望表“团队”能够自动更新以下内容：

Table name = Teams: 

Opponent1: 

  Points in favor = 25
  Points against  = 20

Opponent 2: 

   Points in favor = 20
  Points against  = 25

那是什么代码？可能是（有一些伪代码）：

• 如果得分1大于得分2
  • 将score1添加到表“team”中的“pointsfavor”字段到opponent1
  • 并将$ score2添加到表“团队”中的“pointsagainst”到opponent1

有人能帮助我吗？

Answer 1

假设您的表具有以下结构：

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*/

您的更新语句可能如下所示：

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 game.id = 10;