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重复键的Mysql group_concat和1个查询中多列的重复计数(查询优化)

coder 2023-10-05 原文

这个问题是关于查询优化,以避免通过 PHP 多次调用数据库。

所以这是场景,我有两个表,一个包含您可以称之为引用表的信息,另一个是数据表,字段 key1key2 在两个表,基于这些字段,我们可以加入它们。

我不知道查询是否可以比我现在做的更简单,我想实现的是:

I would like to find distinct key1,key2,info1,info2 from main_info table, whenever serial value is less than 10 and key1,key2 of both table matches, and then group them by info1,info2, while grouping count the repeated key1,key2 for duplicates of info1,info2 fields and group_concat those keys

main_info的内容

MariaDB [demos]> select * from main_info;
+------+------+-------+-------+----------+
| key1 | key2 | info1 | info2 | date     |
+------+------+-------+-------+----------+
|    1 |    1 |    15 |    90 | 20120501 |
|    1 |    2 |    14 |    92 | 20120601 |
|    1 |    3 |    15 |    82 | 20120801 |
|    1 |    4 |    15 |    82 | 20120801 |
|    1 |    5 |    15 |    82 | 20120802 |
|    2 |    1 |    17 |    90 | 20130302 |
|    2 |    2 |    17 |    90 | 20130302 |
|    2 |    3 |    17 |    90 | 20130302 |
|    2 |    4 |    16 |    88 | 20130601 |
+------+------+-------+-------+----------+
9 rows in set (0.00 sec) 

product1 的内容

MariaDB [demos]> select * from product1;
+------+------+--------+--------------+
| key1 | key2 | serial | product_data |
+------+------+--------+--------------+
|    1 |    1 |      0 | NaN          |
|    1 |    1 |      1 | NaN          |
|    1 |    1 |      2 | NaN          |
|    1 |    1 |      3 | NaN          |
|    1 |    2 |      0 | 12.556       |
|    1 |    2 |      1 | 13.335       |
|    1 |    3 |      1 | NaN          |
|    1 |    3 |      2 | 13.556       |
|    1 |    3 |      3 | 14.556       |
|    1 |    4 |      3 | NaN          |
|    1 |    5 |      3 | NaN          |
|    2 |    1 |      0 | 12.556       |
|    2 |    1 |      1 | 13.553       |
|    2 |    1 |      2 | NaN          |
|    2 |    2 |     12 | 129          |
|    2 |    3 |     22 | NaN          |
+------+------+--------+--------------+
16 rows in set (0.00 sec)

通过 PHP,我在当前上下文 serial 中对表 main_info 的字段 info1info2 进行分组,表product1product_data,一个接一个多次(如你所见,这里我运行了两次查询)

对于字段serial - 第一个查询

MariaDB [demos]> select * , count(*) as serial_count,GROUP_CONCAT(key1,' ',key2) as serial_ids from 
    -> (
    -> SELECT distinct 
    -> if(b.serial  < 10,a.key1,null) AS `key1`,
    -> if(b.serial  < 10,a.key2,null) AS `key2`,
    -> if(b.serial  < 10,a.info1,null) AS `info1`, 
    ->         if(b.serial  < 10,a.info2,null) AS `info2`
    -> FROM main_info a inner join product1 b on  a.key1 = b.key1 AND a.key2= b.key2
    -> ) as sub group by info1,info2
    -> ;
+------+------+-------+-------+--------------+-------------+
| key1 | key2 | info1 | info2 | serial_count | serial_ids  |
+------+------+-------+-------+--------------+-------------+
| NULL | NULL |  NULL |  NULL |            1 | NULL        |
|    1 |    2 |    14 |    92 |            1 | 1 2         |
|    1 |    3 |    15 |    82 |            3 | 1 3,1 4,1 5 |
|    1 |    1 |    15 |    90 |            1 | 1 1         |
|    2 |    1 |    17 |    90 |            1 | 2 1         |
+------+------+-------+-------+--------------+-------------+
5 rows in set (0.00 sec)

对于字段 product_data - 第二个查询

MariaDB [demos]> select * , count(*) as product_data_count,GROUP_CONCAT(key1,' ',key2) as product_data_ids from 
    -> (
    -> SELECT distinct 
    -> if(b.product_data IS NOT NULL,a.key1,null) AS `key1`,
    -> if(b.product_data IS NOT NULL,a.key2,null) AS `key2`,
    -> if(b.product_data IS NOT NULL,a.info1,null) AS `info1`, 
    ->         if(b.product_data IS NOT NULL,a.info2,null) AS `info2`
    -> FROM main_info a inner join product1 b on  a.key1 = b.key1 AND a.key2= b.key2
    -> ) as sub group by info1,info2
    -> ;
+------+------+-------+-------+--------------------+------------------+
| key1 | key2 | info1 | info2 | product_data_count | product_data_ids |
+------+------+-------+-------+--------------------+------------------+
|    1 |    2 |    14 |    92 |                  1 | 1 2              |
|    1 |    3 |    15 |    82 |                  3 | 1 3,1 4,1 5      |
|    1 |    1 |    15 |    90 |                  1 | 1 1              |
|    2 |    2 |    17 |    90 |                  3 | 2 2,2 3,2 1      |
+------+------+-------+-------+--------------------+------------------+
4 rows in set (0.01 sec)

我想使用一个查询获得这样的输出,Group by info1, info2

+------+------+-------+-------+--------------+-------------+--------------------+------------------+
| key1 | key2 | info1 | info2 | serial_count | serial_ids  | product_data_count | product_data_ids |
+------+------+-------+-------+--------------+-------------+--------------------+------------------+
| NULL | NULL |  NULL |  NULL |            1 | NULL        |               NULL | NULL             |
|    1 |    2 |    14 |    92 |            1 | 1 2         |                  1 | 1 2              |
|    1 |    3 |    15 |    82 |            3 | 1 3,1 4,1 5 |                  3 | 1 3,1 4,1 5      |
|    1 |    1 |    15 |    90 |            1 | 1 1         |                  1 | 1 1              |
|    2 |    1 |    17 |    90 |            1 | 2 1         |                  3 | 2 2,2 3,2 1      |
+------+------+-------+-------+--------------+-------------+--------------------+------------------+

表格结构如下

DROP TABLE IF EXISTS `main_info`;
CREATE TABLE `main_info` (
  `key1` int(11) NOT NULL,
  `key2` int(11) NOT NULL,
  `info1` int(11) NOT NULL,
  `info2` int(11) NOT NULL,
  `date` int(11) NOT NULL
) ENGINE=MyISAM DEFAULT CHARSET=latin1;


LOCK TABLES `main_info` WRITE;
INSERT INTO `main_info` VALUES (1,1,15,90,20120501),(1,2,14,92,20120601),(1,3,15,82,20120801),(1,4,15,82,20120801),(1,5,15,82,20120802),(2,1,17,90,20130302),(2,2,17,90,20130302),(2,3,17,90,20130302),(2,4,16,88,20130601);
UNLOCK TABLES;


DROP TABLE IF EXISTS `product1`;
CREATE TABLE `product1` (
  `key1` int(11) NOT NULL,
  `key2` int(11) NOT NULL,
  `serial` int(11) NOT NULL,
  `product_data` varchar(1000) DEFAULT NULL
) ENGINE=MyISAM DEFAULT CHARSET=latin1;


LOCK TABLES `product1` WRITE;
INSERT INTO `product1` VALUES (1,1,0,'NaN'),(1,1,1,'NaN'),(1,1,2,'NaN'),(1,1,3,'NaN'),(1,2,0,'12.556'),(1,2,1,'13.335'),(1,3,1,'NaN'),(1,3,2,'13.556'),(1,3,3,'14.556'),(1,4,3,'NaN'),(1,5,3,'NaN'),(2,1,0,'12.556'),(2,1,1,'13.553'),(2,1,2,'NaN'),(2,2,12,'129'),(2,3,22,'NaN');
UNLOCK TABLES;

有人请帮助我在一次查询中获得结果。

最佳答案

如何将您的两个查询与 JOIN 结合起来?

SQL:

 SELECT
    tbl1.key1, tbl1.key2, tbl1.info1, tbl1.info2, tbl1.serial_count, tbl1.serial_ids,
    tbl2.product_data_count, tbl2.product_data_ids
 FROM 
 (
select * , count(*) as serial_count,GROUP_CONCAT(key1,' ',key2) as serial_ids from 
 (
 SELECT distinct 
 if(b.serial  < 10,a.key1,null) AS `key1`,
 if(b.serial  < 10,a.key2,null) AS `key2`,
 if(b.serial  < 10,a.info1,null) AS `info1`, 
         if(b.serial  < 10,a.info2,null) AS `info2`
 FROM main_info a inner join product1 b on  a.key1 = b.key1 AND a.key2= b.key2
 ) as sub group by info1,info2
 ) tbl1
 LEFT OUTER JOIN 
 (
select * , count(*) as product_data_count,GROUP_CONCAT(key1,' ',key2) as product_data_ids from 
 (
 SELECT distinct 
 if(b.product_data IS NOT NULL,a.key1,null) AS `key1`,
 if(b.product_data IS NOT NULL,a.key2,null) AS `key2`,
 if(b.product_data IS NOT NULL,a.info1,null) AS `info1`, 
         if(b.product_data IS NOT NULL,a.info2,null) AS `info2`
 FROM main_info a inner join product1 b on  a.key1 = b.key1 AND a.key2= b.key2
 ) as sub group by info1,info2
 ) tbl2
 ON tbl1.info1 = tbl2.info1 AND tbl1.info2 = tbl2.info2
 ORDER BY 3,4
 ;

输出:

mysql>  SELECT
    -> tbl1.key1, tbl1.key2, tbl1.info1, tbl1.info2, tbl1.serial_count, tbl1.serial_ids,
    -> tbl2.product_data_count, tbl2.product_data_ids
    ->  FROM
    ->  (
    -> select * , count(*) as serial_count,GROUP_CONCAT(key1,' ',key2) as serial_ids from
    ->  (
    ->  SELECT distinct
    ->  if(b.serial  < 10,a.key1,null) AS `key1`,
    ->  if(b.serial  < 10,a.key2,null) AS `key2`,
    ->  if(b.serial  < 10,a.info1,null) AS `info1`,
    ->          if(b.serial  < 10,a.info2,null) AS `info2`
    ->  FROM main_info a inner join product1 b on  a.key1 = b.key1 AND a.key2= b.key2
    ->  ) as sub group by info1,info2
    ->  ) tbl1
    ->  LEFT OUTER JOIN
    ->  (
    -> select * , count(*) as product_data_count,GROUP_CONCAT(key1,' ',key2) as product_data_ids from
    ->  (
    ->  SELECT distinct
    ->  if(b.product_data IS NOT NULL,a.key1,null) AS `key1`,
    ->  if(b.product_data IS NOT NULL,a.key2,null) AS `key2`,
    ->  if(b.product_data IS NOT NULL,a.info1,null) AS `info1`,
    ->          if(b.product_data IS NOT NULL,a.info2,null) AS `info2`
    ->  FROM main_info a inner join product1 b on  a.key1 = b.key1 AND a.key2= b.key2
    ->  ) as sub group by info1,info2
    ->  ) tbl2
    ->  ON tbl1.info1 = tbl2.info1 AND tbl1.info2 = tbl2.info2
    ->  ORDER BY 3,4
    ->  ;
+------+------+-------+-------+--------------+-------------+--------------------+------------------+
| key1 | key2 | info1 | info2 | serial_count | serial_ids  | product_data_count | product_data_ids |
+------+------+-------+-------+--------------+-------------+--------------------+------------------+
| NULL | NULL |  NULL |  NULL |            1 | NULL        |               NULL | NULL             |
|    1 |    2 |    14 |    92 |            1 | 1 2         |                  1 | 1 2              |
|    1 |    3 |    15 |    82 |            3 | 1 3,1 4,1 5 |                  3 | 1 3,1 4,1 5      |
|    1 |    1 |    15 |    90 |            1 | 1 1         |                  1 | 1 1              |
|    2 |    1 |    17 |    90 |            1 | 2 1         |                  3 | 2 2,2 3,2 1      |
+------+------+-------+-------+--------------+-------------+--------------------+------------------+
5 rows in set (0.01 sec)

mysql>  select version();
+-----------------+
| version()       |
+-----------------+
| 10.1.10-MariaDB |
+-----------------+
1 row in set (0.00 sec)

关于重复键的Mysql group_concat和1个查询中多列的重复计数(查询优化),我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/35538092/

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