Question

我之前问过类似的问题，但是我意识到我想要的输出完全不同。

我有以下查询

SELECT LEVEL, COUNT(*) AS total FROM admin_xxx
GROUP BY LEVEL ORDER BY total DESC LIMIT 10

表格输出

Level  Total
4       27
3       24
7       19
5       10
8       9
6       7
1       5
2       3

现在我只想用单词而不是数字来重命名实际级别。

我想将其作为输出

Level     Total
Bronze      27
Silver      24
Gold        19
Gold2       10
Gold3       9
Gold4       7
Gold5       5
Gold6       3

每10个级别都有一个单独的级别名称。

我尝试了以下操作，但语法错误

SELECT LEVEL, COUNT(*) AS total FROM admin_xxx
CASE
WHEN LEVEL = 1 THEN "Bronze",
etc...
WHEN LEVEL = 10 THEN "Gold10"
  END as LEVEL

GROUP BY LEVEL ORDER BY total DESC LIMIT 10

Answer 1

将您的GROUP BY更改为

GROUP BY (
    CASE
        WHEN LEVEL = 1 THEN "Bronze",
        etc...
        WHEN LEVEL = 10 THEN "Gold10"
    END
)

您的SELECT上也存在语法错误

SELECT (
    CASE
        WHEN LEVEL = 1 THEN "Bronze",
        etc...
        WHEN LEVEL = 10 THEN "Gold10"
    END
) AS LEVEL
     , COUNT(*) AS total 
FROM admin_xxx
GROUP BY (
    CASE
        WHEN LEVEL = 1 THEN "Bronze",
        etc...
        WHEN LEVEL = 10 THEN "Gold10"
    END
)
ORDER BY total DESC LIMIT 10

Answer 2

您的from子句位置错误

  SELECT 
      CASE
        WHEN LEVEL = 1 THEN "Bronze" 

        WHEN LEVEL = 10 THEN "Gold10"
      END as  LEVEL
    , COUNT(*) AS total 
  FROM admin_xxx
  GROUP BY LEVEL ORDER BY total DESC LIMIT 10

Answer 3

您还可以将您的级别/标签分离到另一个表，并且可以将它们连接起来。例如：

SELECT levels.level_label, COUNT(*) AS total 
FROM admin_xxx
LEFT JOIN levels ON levels.label_value = admin_xxx.level
GROUP BY levels.level_label ORDER BY total DESC LIMIT 10

这是级别表：

id  level_label     label_value
1   Bronze          10
2   Silver          9
3   Gold            1
4   Gold2           2
5   Gold3           3
6   Gold4           4
7   Gold5           5
8   Gold6           6
9   Gold7           7
10  Gold8           8

Answer 4

请尝试：显然，您应按照以下方式使用pagename来获得所需的输出

CASE

带COUNT个查询的MySQL CASE

4 个答案: