具有动态列的单表MySQL透视

我想通过mysql透视表将mysql表的行转换为列 我的输入表。 我的输入表包含以下格式的数据

Area    Status   User
-----------------------
1       Active   user1
1       Failed   user2
1       Success  user4
2       Active   user2
2       Failed   user3
2       Success  user4

我想要的输出格式如下

---

因为我不知道用户的确切数量，所以我只想通过动态列对其进行透视。

在您的情况下，如果您有一个单独的用户表，您可以轻松地在用户表和状态表之间进行笛卡尔积，并进行透视。。如果你需要进一步的帮助，请告诉我

在我下面的一篇关于销售报表透视schenerio的博文中，我使用动态日历表生成带有订单类别表的笛卡尔产品。。

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我有另一个可以运行的示例，来自

product_id  supplier_id number      price
p1          s1          2           2.12
p1          s2          3           3.12
p2          s1          4           4.12

到

这里的“supplier_id”是动态的，它可能是100万个大数据集中的一个小数据集。因此可能有supplier1、supplier99或supplier999，这取决于源表中的内容。 首先，让我们创建源表：

CREATE TABLE test
(
    product_id varchar(10),
    supplier_id varchar(10),
    number int(11),
    price decimal(10,2)
);
INSERT INTO test (product_id, supplier_id, number, price) VALUES ('p1', 's1', 2, 2.12);
INSERT INTO test (product_id, supplier_id, number, price) VALUES ('p1', 's2', 3, 3.12);
INSERT INTO test (product_id, supplier_id, number, price) VALUES ('p2', 's1', 4, 4.12);

我不认为一个select就可以做到这一点，因此需要临时表和列，下面的代码就是您需要的：

DROP TABLE IF EXISTS  final_data;
DROP TABLE IF EXISTS  temp_data;
CREATE  TEMPORARY TABLE temp_data
    SELECT
           product_id,
           IF(@productid = product_id, @rownum := @rownum + 1, @rownum := 1) seller_number,
           @productid := product_id,
           supplier_id,
           number,
           price
    FROM
         test
           CROSS JOIN (SELECT @rownum := 0) r
           CROSS JOIN (SELECT @productid:="") n
    ORDER BY
             product_id ASC;

ALTER TABLE temp_data ADD PRIMARY KEY(product_id, seller_number);
ALTER TABLE temp_data ADD INDEX (seller_number);

#Dynamic Pivot starts via prepared statements
#Step 1: Dynamily create colum names for sql
#Field supplier_id
SET @sql = NULL;
SELECT
       GROUP_CONCAT(DISTINCT
                    CONCAT(
                      ' MAX(IF( seller_number= ''',
                      seller_number,
                      ''', supplier_id, NULL)) AS ',
                      CONCAT("supplier_id", seller_number)
                        )
           ) INTO @sql
FROM temp_data;

#Field number
SELECT
       CONCAT(@sql, ', ',
              GROUP_CONCAT(DISTINCT
                           CONCAT(
                             ' MAX(IF( seller_number= ''',
                             seller_number,
                             ''', number, NULL)) AS ',
                             CONCAT("number", seller_number)
                               )
                  ) )INTO @sql
FROM temp_data;

#Field price
SELECT
       CONCAT(@sql, ', ',
              GROUP_CONCAT(DISTINCT
                           CONCAT(
                             ' MAX(IF( seller_number= ''',
                             seller_number,
                             ''', price, NULL)) AS ',
                             CONCAT("price", seller_number)
                               )
                  ) )INTO @sql
FROM temp_data;

#Step 2: Add fields to group by query
SET @sql = CONCAT(' create table final_data as (SELECT
                        product_id,
                        ', @sql, '
                    FROM
                        temp_data
                    GROUP BY
                        product_id)  ');

PREPARE stmt FROM @sql;
EXECUTE stmt;
DROP TABLE IF EXISTS  temp_data;

---

研究其他Q&As标记的“透视表”。

CREATE TABLE test
(
    product_id varchar(10),
    supplier_id varchar(10),
    number int(11),
    price decimal(10,2)
);
INSERT INTO test (product_id, supplier_id, number, price) VALUES ('p1', 's1', 2, 2.12);
INSERT INTO test (product_id, supplier_id, number, price) VALUES ('p1', 's2', 3, 3.12);
INSERT INTO test (product_id, supplier_id, number, price) VALUES ('p2', 's1', 4, 4.12);

DROP TABLE IF EXISTS  final_data;
DROP TABLE IF EXISTS  temp_data;
CREATE  TEMPORARY TABLE temp_data
    SELECT
           product_id,
           IF(@productid = product_id, @rownum := @rownum + 1, @rownum := 1) seller_number,
           @productid := product_id,
           supplier_id,
           number,
           price
    FROM
         test
           CROSS JOIN (SELECT @rownum := 0) r
           CROSS JOIN (SELECT @productid:="") n
    ORDER BY
             product_id ASC;

ALTER TABLE temp_data ADD PRIMARY KEY(product_id, seller_number);
ALTER TABLE temp_data ADD INDEX (seller_number);

#Dynamic Pivot starts via prepared statements
#Step 1: Dynamily create colum names for sql
#Field supplier_id
SET @sql = NULL;
SELECT
       GROUP_CONCAT(DISTINCT
                    CONCAT(
                      ' MAX(IF( seller_number= ''',
                      seller_number,
                      ''', supplier_id, NULL)) AS ',
                      CONCAT("supplier_id", seller_number)
                        )
           ) INTO @sql
FROM temp_data;

#Field number
SELECT
       CONCAT(@sql, ', ',
              GROUP_CONCAT(DISTINCT
                           CONCAT(
                             ' MAX(IF( seller_number= ''',
                             seller_number,
                             ''', number, NULL)) AS ',
                             CONCAT("number", seller_number)
                               )
                  ) )INTO @sql
FROM temp_data;

#Field price
SELECT
       CONCAT(@sql, ', ',
              GROUP_CONCAT(DISTINCT
                           CONCAT(
                             ' MAX(IF( seller_number= ''',
                             seller_number,
                             ''', price, NULL)) AS ',
                             CONCAT("price", seller_number)
                               )
                  ) )INTO @sql
FROM temp_data;

#Step 2: Add fields to group by query
SET @sql = CONCAT(' create table final_data as (SELECT
                        product_id,
                        ', @sql, '
                    FROM
                        temp_data
                    GROUP BY
                        product_id)  ');

PREPARE stmt FROM @sql;
EXECUTE stmt;
DROP TABLE IF EXISTS  temp_data;