mysql 重复单号统计

爱被打了一巴掌 2024-04-20 22:16 28阅读 0赞

任务： 增加重复件统计分析： 统计展示选择时间范围内重复1次、重复2次、重复3次、重复4次、重复5次及以上的数据量

![9a0ef55b232d44c38c05b2f52bc5112a.png][]

### 17、统计出现的重复次数 ###

增加重复件统计分析： 统计展示选择时间范围内重复1次、重复2次、重复3次、重复4次、重复5次及以上的数据量。

#### 1，建表 ####

DROP TABLE IF EXISTS repeat_num;
    CREATE TABLE repeat_num(
      id INT NOT NULL AUTO_INCREMENT,
      create_date DATE,
      content VARCHAR(500),
      nums VARCHAR(500),
      PRIMARY KEY(id)
    );

#### 2，插入数据 ####

INSERT INTO repeat_num VALUES
    (1, '2024-01-01', '投诉', '1'),
    (2, '2024-01-02', '举报', '1,2'),
    (3, '2024-01-03', '申告', '1,2,3'),
    (4, '2024-01-04', '提醒', '1,2,3,4'),
    (5, '2024-01-05', '告知', '1,2,3,4,5'),
    (6, '2024-01-06', '预警', '1,2,3,4,5,6'),
    (7, '2024-01-07', '投诉', '2,3'),
    (8, '2024-01-08', '举报', '3'),
    (9, '2024-01-09', '举报', '4,5,6'),
    (10, '2024-01-10', '举报', '2,5,1,3'),
    (11, '2024-01-11', '举报', '7,8,9'),
    (12, '2024-01-12', '申诉', '1,2,3,4,5,6,8'),
    (13, '2024-01-13', '申诉', '2,6'),
    (14, '2024-01-14', '申诉', '1,3,4,5,6'),
    (15, '2024-01-15', '申诉', '1,3,5,6,7,8,9'),
    (16, '2024-01-16', '申诉', '5,7,8,9,10,11,13'),
    (17, '2024-01-17', '申诉', '7,8,9,10'),
    (18, '2024-01-18', '提醒', '7,8,9,10,14'),
    (19, '2024-01-19', '告知', '5,7,8,9,10'),
    (20, '2024-01-20', '告知', '4,5,6,7,8,9,11,12'),
    (21, '2024-01-21', '预警', '3,5'),
    (22, '2024-01-22', '预警', '8,9,11');

#### 3，sql ####

##### 1，先结算长度： #####

-- 先计算原来的长度，然后用replace 替换到目标值，得到的长度，相减就是目标长度。 如果目标是多字符串的
    SELECT LENGTH('1,2,3,4,5,6') - 
    LENGTH(REPLACE('1,2,3,4,5,6', ',', '')) AS count_commas;

多字符间隔处理：

-- 多字符的，计算结果要除以自身长度
    SELECT  (LENGTH('best wish for you! best wish for you!') - 
    LENGTH( REPLACE ('best wish for you! best wish for you', 'for', '')))/ 
    LENGTH('for')  AS repeat_num;
    
    
    -- 向下取整
    SELECT  FLOOR((LENGTH('best wish for you! best wish for you!') - 
    LENGTH( REPLACE ('best wish for you! best wish for you', 'for', '')))/ 
    LENGTH('for'))  AS repeat_num;

##### 2，计算重复次数： #####

SELECT *, (LENGTH(nums) - LENGTH(REPLACE(nums, ',', ''))  + 1) 
    AS  repeat_count 
     FROM repeat_num ;

##### 3，进行统计： #####

-- 统计：
    SELECT repeat_count, SUM(repeat_count) repeat_sum
    FROM (
     SELECT *, (LENGTH(nums) - LENGTH(REPLACE(nums, ',', ''))  + 1) AS  repeat_count 
     FROM repeat_num  
    ) AS temp GROUP BY repeat_count;

##### 4，统计以上的： #####

-- 统计 重复1次、重复2次、重复3次、重复4次、重复5次及以上 
     -- 以上的，又要聚合统计，得单独写
    SELECT  repeat_count, SUM(repeat_count) repeat_sum
    	FROM (
    	 SELECT *, (LENGTH(nums) - LENGTH(REPLACE(nums, ',', ''))  + 1) AS  repeat_count 
    	 FROM repeat_num  
    	) AS temp WHERE repeat_count <= 5
    	GROUP BY repeat_count
      UNION  
     SELECT  6 AS repeat_count, SUM(repeat_count) repeat_sum
    	FROM (
    	 SELECT *, (LENGTH(nums) - LENGTH(REPLACE(nums, ',', ''))  + 1) AS  repeat_count 
    	 FROM repeat_num  
    	) AS temp WHERE repeat_count > 5;

#### 2，用函数的方式： ####

##### 知识点： #####

**SUBSTRING(s,n,len)**带有len参数的格式，从字符串s返回一个长度同 len字符相同的子字符串，起始于位置n，也可能对n使用一个负值。假若这样，则子字符串的位置起始于字符串结尾的n字符，即倒数第n个字符，而不是字符串的开头位置。

【例 1】使用SUBSTRING函数获取指定位置处的子字符串，输入语句如下：

SELECT SUBSTRING('breakfast', 5) AS coll,
     SUBSTRING('breakfast', 5,3) AS co12,
    SUBSTRING('lunch', -3) AS co13,
    SUBSTRING('lunch', -5, 3)AS col4;

![6b7b1082696a4c8bb233c6eda21a145a.png][]

SUBSTRING('breakfast',5)返回从第5个位置开始到字符串结尾的子字符串，结果为“kfast”; SUBSTRING(breakfast',5,3)返回从第5个位置开始长度为3的子字符串，结果为“kfa”;

SUBSTRING("unch',-3)返回从结尾开始第3个位置到字符串结尾的子字符串，结果为“nch”; SUBSTRING('lunch',-5,3)返回从结尾开始第5个位置，即字符串开头起，长度为3的子字符串，结果为“lun”。

用SUBSTRING去处理，不断去遍历，判断值符合条件的，就记录下。

##### 函数： #####

DELIMITER //
    
    
    CREATE FUNCTION count_by_symbols(str VARCHAR(255), symbol VARCHAR(10))
      RETURNS INT
      BEGIN
        DECLARE cnt INT DEFAULT 0;
        DECLARE idx INT DEFAULT 1;
        DECLARE len INT;
    
    
        SET len = CHAR_LENGTH(str);
    
    
        WHILE idx <= len DO
          IF SUBSTRING(str, idx, 1) = symbol THEN
            SET cnt = cnt + 1;
          END IF;
          SET idx = idx + 1;
        END WHILE;
    
    
        RETURN cnt;
      END //
    
    
    DELIMITER ;

使用

SELECT  count_by_symbols('a|lin|yan@sd|fd|ds|f', "|") AS count_symbol_num;

如果新建函数保存

##### 报错 #####

This function has none of DETERMINISTIC, NO SQL, or READS SQL DATA in its declaration and binary logging is enabled (you \*might\* want to use the less safe log\_bin\_trust\_function\_creators variable)

SET GLOBAL log_bin_trust_function_creators = 1;

##### 调用： #####

SELECT *, (count_by_symbols(nums, ',')   + 1) AS  repeat_num 
     FROM repeat_num ;

##### 统计： #####

SELECT  repeat_count, SUM(repeat_count) repeat_sum
    	FROM (
    	 SELECT *, (count_by_symbols(nums, ',')   + 1) AS  repeat_count 
    	 FROM repeat_num  
    	) AS temp WHERE repeat_count <= 5
    	GROUP BY repeat_count
      UNION  
     SELECT  6 AS repeat_count, SUM(repeat_count) repeat_sum
    	FROM (
    	 SELECT *, (count_by_symbols(nums, ',')   + 1) AS  repeat_count 
    	 FROM repeat_num  
    	) AS temp WHERE repeat_count > 5;

### 总结： ###

推荐用第一种方式，第二种，得看环境是否支持自定义函数或者过程。这种还好，如果要根据repeat\_num去聚合的话，这种要聚合的话，这个要进行统计，就很麻烦了，用sql的话，得变成行转列，然后再进行统计。java的话，得把内容进行分离后，再重新聚合。

上一篇： 《[mysql 日环比 统计][mysql _]》

下一篇： 《[mysql 索引][mysql]》

[9a0ef55b232d44c38c05b2f52bc5112a.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/20/d25aa857a64245f28da8ae8a659c8207.png
[6b7b1082696a4c8bb233c6eda21a145a.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/20/7aeb62b77768462eaa99b6e8ac0556a1.png
[mysql _]: https://blog.csdn.net/qq_35461948/article/details/137807712?csdn_share_tail=%7B%22type%22%3A%22blog%22%2C%22rType%22%3A%22article%22%2C%22rId%22%3A%22137807712%22%2C%22source%22%3A%22qq_35461948%22%7D
[mysql]: https://blog.csdn.net/qq_35461948/article/details/137086896?csdn_share_tail=%7B%22type%22%3A%22blog%22%2C%22rType%22%3A%22article%22%2C%22rId%22%3A%22137086896%22%2C%22source%22%3A%22qq_35461948%22%7D