Question

这个表包含1.2mill的结果，我无法编辑它，因为有些应用程序我也没有源代码来访问它。我想添加一个数量字段，但我不能。

以下是我正在使用的查询：

  SELECT SUM(assets.hourlyEarnings) as earnings, 
         assets_inventory.uid
    FROM (assets)
    JOIN assets_inventory ON assets.id = assets_inventory.assetID
   WHERE assets_inventory.uid IN (SELECT users.uid 
                                    FROM users 
                                   WHERE users.assetTime < 1305350756)
GROUP BY uid

有许多重复记录。

这是表格：

CREATE TABLE IF NOT EXISTS assets_inventory (
  id int(11) NOT NULL AUTO_INCREMENT,
  uid bigint(20) NOT NULL,
  assetID int(11) NOT NULL,
  PRIMARY KEY (id),
  KEY uid (uid)
) ENGINE=InnoDB  DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci AUTO_INCREMENT=1231992 ;

平均而言，我需要6-7秒才能得出结果，任何提高速度的建议都将受到赞赏！

Answer 1

如果您需要所有uid值的列表，是否有相关收入：

   SELECT DISTINCT
          ai.uid,
          COALESCE(x.earnings, 0) AS earnings
     FROM ASSETS_INVENTORY ai
LEFT JOIN (SELECT t.id,
                  SUM(t.hourlyearnings) AS earnings
             FROM ASSETS t
         GROUP BY t.id) x ON x.id = ai.assetid
    WHERE EXISTS (SELECT NULL
                    FROM USERS u
                   WHERE u.uid = ai.uid
                     AND u.assettime < 1305350756)

否则：

  SELECT ai.uid,
         SUM(a.hourlyearnings) AS earnings
    FROM ASSETS_INVENTORY ai
    JOIN ASSETS a ON a.id = ai.assetid
   WHERE EXISTS (SELECT NULL
                   FROM USERS u
                  WHERE u.uid = ai.uid
                    AND u.assettime < 1305350756)
GROUP BY ai.uid

...或：

  SELECT ai.uid,
         SUM(a.hourlyearnings) AS earnings
    FROM ASSETS_INVENTORY ai
    JOIN ASSETS a ON a.id = ai.assetid
    JOIN USERS u ON u.uid = ai.uid
                AND u.assettime < 1305350756
GROUP BY ai.uid

大表查询优化（mysql）

1 个答案: