Question

我选择非常简单，让我们说：

SELECT COUNT(added) FROM users WHERE added < "2015-07-30"

我是否可以通过一些简单的方式运行此选择，不仅仅是针对给定的日期，还有，比如说，7天，每一行显示计算到特定日期？

编辑：这是我构建表格的SQL：

CREATE TABLE users (
id INT(6) UNSIGNED AUTO_INCREMENT PRIMARY KEY,
 added DATE
);

INSERT INTO users (added) VALUES ("2015-07-30");
INSERT INTO users (added) VALUES ("2015-07-29");
INSERT INTO users (added) VALUES ("2015-07-28");
INSERT INTO users (added) VALUES ("2015-07-21");
INSERT INTO users (added) VALUES ("2015-07-26");
INSERT INTO users (added) VALUES ("2015-07-25");
INSERT INTO users (added) VALUES ("2015-07-24");
INSERT INTO users (added) VALUES ("2015-07-23");
INSERT INTO users (added) VALUES ("2015-07-29");
INSERT INTO users (added) VALUES ("2015-07-22");
INSERT INTO users (added) VALUES ("2015-07-20");
INSERT INTO users (added) VALUES ("2014-02-10");

我希望结果如下：

    DATE   | Count |
--------------------                   
2015-07-30 |  12   |
2015-07-29 |  11   |   
2015-07-28 |  10   |
2015-07-27 |   9   |
2015-07-26 |   9   |
2015-07-25 |   8   |
2015-07-24 |   7   |

Answer 1

我想你想要这样的东西：

SELECT
  SUM(added >= CURRENT_DATE() - INTERVAL 14 DAY) AS last_14_days,
  SUM(added >= CURRENT_DATE() - INTERVAL 7 DAY) AS last_7_days,
  SUM(added = CURRENT_DATE()) AS today
FROM users
WHERE
  added >= CURRENT_DATE() - INTERVAL 14 DAY

您还可以使用它来计算＆lt;之前的所有记录。 “2015-07-30”和过去7天，但会有不好的表现，我建议你改用内联查询：

SELECT
  (SELECT COUNT(added) FROM users WHERE added < "2015-07-30") AS before_30,
  (SELECT COUNT(added) FROM users WHERE added >= "2015-09-08") AS last_7

或UNION查询：

SELECT "Before 30" as Interval, COUNT(*) AS total
FROM users WHERE added < "2015-07-30"
UNION ALL
SELECT "Last 7" as Interval, COUNT(*) AS total
FROM users WHERE added >= "2015-09-08"

修改

根据您的评论，您需要使用GROUP BY查询。如果添加的是日期字段（没有时间信息），则可以使用此查询：

SELECT added, COUNT(*) FROM users WHERE added >= CURRENT_DATE() - INTERVAL 7 DAY GROUP BY added

修改

这应该是你要找的东西：

SELECT d.added, COUNT(*) FROM (SELECT DISTINCT added FROM users WHERE added BETWEEN "2015-07-30" - INTERVAL 30 DAY AND "2015-07-30") AS d INNER JOIN users ON users.added <= d.added GROUP BY d.added ORDER BY `d`.`added` DESC

SQLFiddle here

在MySQL中对多个数据运行相同SELECT的最简单方法

1 个答案: