Question

这是来自带汇总的mysql的示例结果

|country | region | value  |
|--------|--------|--------|
|   us   |  west  |   5    |
|   us   |  east  |   15   |
|   us   |  north |   10   |
|   us   |  total |   30   |
|   uk   |  west  |   3    |
|   uk   |  east  |   2    |
|   uk   |  north |   1    |
|   uk   |  total |   6    |
|  total |  total |   36   |

我想像这样排序值列，保留总行位置

ASC

|   us   |  west  |   5    |
|   us   |  north |   10   |
|   us   |  east  |   15   |
|   us   |  total |   30   |
|   uk   |  north |   1    |
|   uk   |  east  |   2    |
|   uk   |  west  |   3    |
|   uk   |  total |   6    |
|  total |  total |   36   |

DESC

|   us   |  east  |   15   |
|   us   |  north |   10   |
|   us   |  west  |   5    |
|   us   |  total |   30   |
|   uk   |  west  |   3    |
|   uk   |  east  |   2    |
|   uk   |  north |   1    |
|   uk   |  total |   6    |
|  total |  total |   36   |

这是一个查询示例：

SELECT *
FROM (
  SELECT 
  COALESCE(country, 'total') AS country, 
  COALESCE(region, 'total' ) AS region, 
  SUM('value'), 
  FROM table 
  GROUP BY country ASC, region ASC 
  WITH ROLLUP
) t
ORDER BY ... maybe something to do here ...

也许基于正则表达式的排序顺序？或者使用mysql字符串函数？

我不知道如何解决我的问题

感谢提前寻求帮助

...

在你的帮助和经过一些个人反思之后我想我现在有一个很好的方法来做这件事

SELECT *
FROM (
   SELECT 
   IF(IFNULL(country, 1),'total',NULL) AS country,
   IF(IFNULL(region, 1),'total',NULL) AS region,
   COALESCE(country, 'Total') AS country1, 
   COALESCE(region, 'Total') AS region1, 
   SUM(value) as `value to sort`
   FROM data_table
   GROUP BY country, region WITH ROLLUP
) t 
ORDER BY  
country IS NULL DESC, 
country1 ASC, 
region IS NULL DESC, ...

 ... `value to sort` DESC

(or)

 ... `value to sort` ASC

即使使用DESC排序，我总是在聚合和子聚合值之后总计和子总数： - ）

你认为这是一个好方法吗？它在所有情况下都适合我

Answer 1

基于Johan's answer的原始版本：

SELECT *
FROM (
  SELECT 
    COALESCE(country, 'total') AS country,
    COALESCE(region, 'total' ) AS region,
    SUM(`value`) as `value`, 
  FROM `table` 
  GROUP BY country, region WITH ROLLUP
) t
ORDER BY country = 'total', country, region = 'total', `value`

这个技巧的工作方式是，如果country = 'total'列等于country，则表达式'total'的计算结果为1（真），否则计算结果为0（假）。按升序排列，1在0之后。因此，按该表达式排序会强制country列等于'total'的任何行在任何其他列之后排序。

同样，在region = 'total'之前按表达式value排序会强制'total'中值region的任何行在具有相同{{1}的任何其他行之后排序}}，无论他们的country列如何。

同样的技巧也适用于其他comparison operators。例如，如果您想强制使用负值对正值进行排序，则可以按value对行进行排序。

Answer 2

with rollup生成的总计行具有非聚合行的所有零值您可以利用它来强制该行为最后一个（或第一个）。

试试这个，没有测试过，所以我不是百分百确定：

SELECT 
  ti2.country
  , ti2.region
  ,ti2.`value`
FROM table1 to1
INNER JOIN (SELECT 
              t2.country
              ,IFNULL(ti1.region,'subtotal') as country
              ,ti1.`value` 
            FROM (
             SELECT 
              t1.country
              , t1.region
              , SUM(t1.`value`) as `value`
             FROM table1 t1
             WHERE t1.country = to1.country 
             GROUP BY country, region WITH ROLLUP) ti1 ) ti2
ON (ti2.country = to1.country)
GROUP BY country, region WITH ROLLUP
ORDER BY country, region = 'subtotal', region

请注意，order by子句应该进入外部（！）选择，而不是内部选择 （我知道内部选择的顺序在大多数情况下都有效，但是当查询变得复杂时，它会搞砸并让你偏离轨道）
还要注意，依赖行为构建到MySQL的group by子句中的非标准隐式顺序并不是一个好主意;最好坚持使用标准SQL，除非获得明显的好处。

Answer 3

这很棘手！我做了一个（相当大的）假设你有一个countryId列可以在你的源表中使用，它唯一地标识表中的每个国家（所以'us'有countryId = 1，'uk'有countryId = 2等等）。如果你不这样做，你总是可以添加一个：

-- Descending
SELECT *
FROM (
  SELECT 
  COALESCE(country, 'total') AS pays,
  COALESCE(region, 'total' ) AS region,
  SUM(value) as value, 
  (SUM(value) * (CASE WHEN COALESCE(region, 'total') = 'total' THEN 1 ELSE -1 END)   
    + countryId*(SELECT SUM(value) FROM test_table) 
    + CASE WHEN COALESCE(country, 'total') = 'total' 
           THEN (SELECT SUM(value) FROM test_table) ELSE 0 END) as rank1
  FROM test_table 
  GROUP BY country, region WITH ROLLUP
) t
ORDER BY rank1 asc;


-- Ascending
SELECT *
FROM (
  SELECT 
  COALESCE(country, 'total') AS pays, 
  COALESCE(region, 'total' ) AS region,
  SUM(value) as value, 
  (SUM(value) + countryId*(SELECT SUM(value) FROM test_table) 
    + CASE WHEN COALESCE(country, 'total') = 'total' 
           THEN (SELECT SUM(value) FROM test_table) ELSE 0 END) as rank1
  FROM table 
  GROUP BY country, region WITH ROLLUP
) t
order by rank1 asc;

不是最漂亮的，当然不是最干净的，但应该帮助你。

汇总后保存总计和小计行位置

3 个答案: