MySQL场站信息结合日历表查询月数据完整性

为了查询MySQL场站信息结合日历表的月数据完整性，可以使用以下步骤：

创建一个日历表，包含所有月份的日期信息，如下：

CREATE TABLE calendar (
    date DATE NOT NULL PRIMARY KEY,
    year INT NOT NULL,
    month INT NOT NULL,
    day INT NOT NULL,
    day_of_week INT NOT NULL,
    day_of_year INT NOT NULL,
    week_of_year INT NOT NULL,
    is_weekend BOOLEAN NOT NULL
);

插入一些示例数据，如下：

INSERT INTO calendar (date, year, month, day, day_of_week, day_of_year, week_of_year, is_weekend)
VALUES ('2022-01-01', 2022, 1, 1, 7, 1, 1, TRUE),
       ('2022-01-02', 2022, 1, 2, 1, 2, 1, TRUE),
       ('2022-01-03', 2022, 1, 3, 2, 3, 1, FALSE),
       ('2022-01-04', 2022, 1, 4, 3, 4, 1, FALSE),
       ('2022-01-05', 2022, 1, 5, 4, 5, 1, FALSE),
       ('2022-01-06', 2022, 1, 6, 5, 6, 1, FALSE),
       ('2022-01-07', 2022, 1, 7, 6, 7, 1, FALSE),
       ('2022-01-08', 2022, 1, 8, 7, 8, 2, TRUE),
       ('2022-01-09', 2022, 1, 9, 1, 9, 2, TRUE),
       ('2022-01-10', 2022, 1, 10, 2, 10, 2, FALSE),
       ('2022-01-11', 2022, 1, 11, 3, 11, 2, FALSE),
       ('2022-01-12', 2022, 1, 12, 4, 12, 2, FALSE),
       ('2022-01-13', 2022, 1, 13, 5, 13, 2, FALSE),
       ('2022-01-14', 2022, 1, 14, 6, 14, 2, FALSE),
       ('2022-01-15', 2022, 1, 15, 7, 15, 3, TRUE),
       ('2022-01-16', 2022, 1, 16, 1, 16, 3, TRUE),
       ('2022-01-17', 2022, 1, 17, 2, 17, 3, FALSE),
       ('2022-01-18', 2022, 1, 18, 3, 18, 3, FALSE),
       ('2022-01-19', 2022, 1, 19, 4, 19, 3, FALSE),
       ('2022-01-20', 2022, 1, 20, 5, 20, 3, FALSE),
       ('2022-01-21', 2022, 1, 21, 6, 21, 3, FALSE),
       ('2022-01-22', 2022, 1, 22, 7, 22, 4, TRUE),
       ('2022-01-23', 2022, 1, 23, 1, 23, 4, TRUE),
       ('2022-01-24', 2022, 1, 24, 2, 24, 4, FALSE),
       ('2022-01-25', 2022, 1, 25, 3, 25, 4, FALSE),
       ('2022-01-26', 2022, 1, 26, 4, 26, 4, FALSE),
       ('2022-01-27', 2022, 1, 27, 5, 27, 4, FALSE),
       ('2022-01-28', 2022, 1, 28, 6, 28, 4, FALSE),
       ('2022-01-29', 2022, 1, 29, 7, 29, 5, TRUE),
       ('2022-01-30', 2022, 1, 30, 1, 30, 5, TRUE),
       ('2022-01-31', 2022, 1, 31, 2, 31, 5, FALSE);

创建一个场站信息表，包含以下字段：

CREATE TABLE station (
    id INT NOT NULL PRIMARY KEY,
    name VARCHAR(255) NOT NULL,
    location VARCHAR(255) NOT NULL,
    start_date DATE NOT NULL,
    end_date DATE NOT NULL
);

插入一些示例数据，如下：

INSERT INTO station (id, name, location, start_date, end_date)
VALUES (1, 'Station A', 'City 1', '2022-01-01', '2022-01-15'),
       (2, 'Station B', 'City 2', '2022-01-10', '2022-01-31'),
       (3, 'Station C', 'City 3', '2022-01-05', '2022-01-20');

使用以下查询语句，查询每个场站在每个月的数据完整性，即在每个月的所有日期范围内，该场站是否有数据：

SELECT s.name, c.year, c.month, COUNT(*) AS days_with_data
FROM station s
JOIN calendar c ON c.date BETWEEN s.start_date AND s.end_date
GROUP BY s.id, c.year, c.month;

查询结果如下：

name        year    month   days_with_data
Station A   2022    1       15
Station B   2022    1       22
Station C   2022    1       16

说明：

Station A 在 1 月份的所有日期范围内有 15 天的数据
Station B 在 1 月份的所有日期范围内有 22 天的数据
Station C 在 1 月份的所有日期范围内有 16 天的数据

这样可以查询MySQL场站信息结合日历表的月数据完整性。