我正在使用 DB Browser for SQLite。我有以下格式的表格:
+-----------+-------------------------------------+
| search_id | search_town |
+-----------+-------------------------------------+
| 1 | town1,town3 |
| 2 | town2,town4,town5 |
| 3 | town3,town5 |
| 4 | town2,town5 |
| 5 | town2,town3,town4 |
+-----------+-------------------------------------+
我想对 town1
到 town5
出现在 search_town
下的次数进行COUNT
,然后根据各自的计数对城镇进行降序排列。到目前为止,我有以下查询:
SELECT SUM(CASE WHEN search_location LIKE '%town01%' THEN 1 ELSE 0 END) AS town01,
SUM(CASE WHEN search_location LIKE '%town02%' THEN 1 ELSE 0 END) AS town02,
SUM(CASE WHEN search_location LIKE '%town03%' THEN 1 ELSE 0 END) AS town03,
SUM(CASE WHEN search_location LIKE '%town04%' THEN 1 ELSE 0 END) AS town04,
SUM(CASE WHEN search_location LIKE '%town05%' THEN 1 ELSE 0 END) AS town05
FROM searches
...但是我无法执行 ORDER BY
,因为城镇及其计数以这种格式输出为列而不是行
+-------+-------+-------+-------+-------+
| town1 | town2 | town3 | town4 | town5 |
+-------+-------+-------+-------+-------+
| 12 | 31 | 12 | 24 | 12 |
+-------+-------+-------+-------+-------+
还有其他方法吗?感谢任何评论。
最佳答案
您正在使用 CASE WHEN
将输出转换为单行,要将其转换为多行,您可以尝试如下操作。
;WITH cte
AS (SELECT *
FROM (VALUES ('Town1'),
('Town2'),
('Town3'),
('Town4'),
('Town5')) T(town))
SELECT Count(*) [Count],
C.town
FROM [TABLE_NAME] T
INNER JOIN cte C
ON T.search_location LIKE '%' + C.town + '%'
GROUP BY C.town
ORDER BY Count(*) DESC
另一种方法可以使用 UNION ALL
。
SELECT *
FROM (SELECT Count(*) s,
'Town1' AS Col
FROM tablename
WHERE search_location LIKE '%town1%'
UNION ALL
SELECT Count(*) s,
'Town2' AS Col
FROM tablename
WHERE search_location LIKE '%town2%'
UNION ALL
SELECT Count(*) s,
'Town3' AS Col
FROM tablename
WHERE search_location LIKE '%town3%'
UNION ALL
SELECT Count(*) s,
'Town4' AS Col
FROM tablename
WHERE search_location LIKE '%town4%'
UNION ALL
SELECT Count(*) s,
'Town5' AS Col
FROM tablename
WHERE search_location LIKE '%town5%') t
ORDER BY s DESC
关于sql - 使用 SQL 查询对计数进行排名,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/54626051/