实现"mysql当前月工作日数"教程
简介
在本教程中，我将向你展示如何在MySQL中实现当前月的工作日数计算。作为一名经验丰富的开发者，我将一步步指导你完成这个任务，并解释每一步需要做什么以及相应的代码。
流程步骤表格
下面是完成任务的流程步骤表格：
| 步骤 | 操作 |
|---|---|
| 1 | 创建一个存储过程 |
| 2 | 计算当前月的总天数 |
| 3 | 计算当前月的周末天数 |
| 4 | 计算当前月的工作日数 |
代码示例
创建存储过程
-- 创建存储过程来计算当前月的工作日数
DELIMITER $$
CREATE PROCEDURE calculate_workdays()
BEGIN
-- 在这里编写后续计算代码
END$$
DELIMITER ;
计算当前月的总天数
-- 计算当前月的总天数
SELECT DAY(LAST_DAY(CURRENT_DATE));
计算当前月的周末天数
-- 计算当前月的周末天数
SELECT COUNT(*)
FROM (
SELECT DAY(d) AS day
FROM (
SELECT CURRENT_DATE + INTERVAL (a.a + (10 * b.a) + (100 * c.a)) DAY AS d
FROM (
SELECT 0 AS a UNION ALL SELECT 1 UNION ALL SELECT 2 UNION ALL SELECT 3 UNION ALL SELECT 4 UNION ALL SELECT 5 UNION ALL SELECT 6 UNION ALL SELECT 7 UNION ALL SELECT 8 UNION ALL SELECT 9
) AS a
CROSS JOIN (
SELECT 0 AS a UNION ALL SELECT 1 UNION ALL SELECT 2 UNION ALL SELECT 3 UNION ALL SELECT 4 UNION ALL SELECT 5 UNION ALL SELECT 6 UNION ALL SELECT 7 UNION ALL SELECT 8 UNION ALL SELECT 9
) AS b
CROSS JOIN (
SELECT 0 AS a UNION ALL SELECT 1 UNION ALL SELECT 2 UNION ALL SELECT 3 UNION ALL SELECT 4 UNION ALL SELECT 5 UNION ALL SELECT 6 UNION ALL SELECT 7 UNION ALL SELECT 8 UNION ALL SELECT 9
) AS c
) a
WHERE d BETWEEN CURRENT_DATE AND LAST_DAY(CURRENT_DATE)
AND DAYOFWEEK(d) IN (1, 7)
) AS weekend_days;
计算当前月的工作日数
-- 计算当前月的工作日数
SELECT DAY(LAST_DAY(CURRENT_DATE)) - COUNT(*)
FROM (
SELECT DAY(d) AS day
FROM (
SELECT CURRENT_DATE + INTERVAL (a.a + (10 * b.a) + (100 * c.a)) DAY AS d
FROM (
SELECT 0 AS a UNION ALL SELECT 1 UNION ALL SELECT 2 UNION ALL SELECT 3 UNION ALL SELECT 4 UNION ALL SELECT 5 UNION ALL SELECT 6 UNION ALL SELECT 7 UNION ALL SELECT 8 UNION ALL SELECT 9
) AS a
CROSS JOIN (
SELECT 0 AS a UNION ALL SELECT 1 UNION ALL SELECT 2 UNION ALL SELECT 3 UNION ALL SELECT 4 UNION ALL SELECT 5 UNION ALL SELECT 6 UNION ALL SELECT 7 UNION ALL SELECT 8 UNION ALL SELECT 9
) AS b
CROSS JOIN (
SELECT 0 AS a UNION ALL SELECT 1 UNION ALL SELECT 2 UNION ALL SELECT 3 UNION ALL SELECT 4 UNION ALL SELECT 5 UNION ALL SELECT 6 UNION ALL SELECT 7 UNION ALL SELECT 8 UNION ALL SELECT 9
) AS c
) a
WHERE d BETWEEN CURRENT_DATE AND LAST_DAY(CURRENT_DATE)
AND DAYOFWEEK(d) NOT IN (1, 7)
) AS workdays;
序列图
sequenceDiagram
participant You
participant Novice Developer
You->>Novice Developer: 传达任务要求
Novice Developer->>You: 开始学习
You->>Novice Developer: 指导创建存储过程
Novice Developer->>You: 创建存储过程
You->>Novice Developer: 指导计算总天数
Novice Developer->>You: 计算总天数
You->>Novice Developer: 指导计算周末天数
Novice Developer->>You: 计算周末天数
You->>Novice Developer: 指导计算工作日数
Novice Developer->>You: 计算工作日数
You->>Novice Developer: 完成
