MySQL实现优雅统计工作日(周一至周五)数据

CREATE TABLE visits (
    id INT PRIMARY KEY AUTO_INCREMENT,
    visit_date DATETIME NOT NULL,   -- 访问时间
    user_id INT,
    page VARCHAR(100)
);

SELECT 
    DATE(visit_date) AS visit_day,
    COUNT(*) AS visit_count
FROM visits
WHERE WEEKDAY(visit_date) <= 4   -- 0~4 周一到周五
GROUP BY DATE(visit_date)
ORDER BY visit_day;

SELECT 
    DATE(visit_date) AS visit_day,
    COUNT(*) AS visit_count
FROM visits
WHERE DAYOFWEEK(visit_date) BETWEEN 2 AND 6   -- 2=周一,6=周五
GROUP BY DATE(visit_date);

SELECT 
    DATE(visit_date) AS visit_day,
    CASE WEEKDAY(visit_date)
        WHEN 0 THEN '周一'
        WHEN 1 THEN '周二'
        WHEN 2 THEN '周三'
        WHEN 3 THEN '周四'
        WHEN 4 THEN '周五'
        ELSE '周末'
    END AS weekday_cn,
    COUNT(*) AS visit_count
FROM visits
WHERE WEEKDAY(visit_date) <= 4
GROUP BY DATE(visit_date);

-- 假设查询2025-05-12到2025-05-18这一周的数据
SELECT DATE(visit_date), COUNT(*)
FROM visits
WHERE visit_date BETWEEN '2025-05-12 00:00:00' AND '2025-05-18 23:59:59'
  AND WEEKDAY(visit_date) <= 4
GROUP BY DATE(visit_date);

-- 创建函数索引（直接对 WEEKDAY(visit_date) 建立索引）
CREATE INDEX idx_visit_weekday ON visits ((WEEKDAY(visit_date)));

SELECT DATE(visit_date), COUNT(*)
FROM visits
WHERE WEEKDAY(visit_date) <= 4
GROUP BY DATE(visit_date);

-- 添加虚拟列（不占用额外存储，实时计算）
ALTER TABLE visits 
ADD COLUMN weekday_val TINYINT 
GENERATED ALWAYS AS (WEEKDAY(visit_date)) STORED;  -- 或 VIRTUAL

-- 为虚拟列创建索引
CREATE INDEX idx_weekday ON visits(weekday_val);

-- 查询时使用虚拟列
SELECT DATE(visit_date), COUNT(*)
FROM visits
WHERE weekday_val <= 4
GROUP BY DATE(visit_date);

CREATE TABLE visits_daily_summary (
    visit_date DATE PRIMARY KEY,
    total_count INT DEFAULT 0,
    weekday_count INT DEFAULT 0,
    weekend_count INT DEFAULT 0,
    updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP
);

INSERT INTO visits_daily_summary (visit_date, total_count, weekday_count)
SELECT 
    DATE(visit_date),
    COUNT(*),
    SUM(WEEKDAY(visit_date) <= 4)
FROM visits
WHERE visit_date >= CURDATE() - INTERVAL 1 DAY
  AND visit_date < CURDATE()
GROUP BY DATE(visit_date)
ON DUPLICATE KEY UPDATE
    total_count = total_count + VALUES(total_count),
    weekday_count = weekday_count + VALUES(weekday_count);

-- 查询 2025年5月 工作日的日均访问量（使用虚拟列方案）
SELECT 
    COUNT(*) / COUNT(DISTINCT DATE(visit_date)) AS avg_weekday_visits
FROM visits
WHERE visit_date >= '2025-05-01' 
  AND visit_date < '2025-06-01'
  AND weekday_val <= 4;   -- 假设已添加虚拟列并建立索引