Question

ORACLE表中的以下结构：

FILE_NAME
-----------
12345_l.tif
12345_m.tif
12345_r.tif
12345_x.tif
12345_y.tif

需要以下结果：

First *_m*
Then *_l*
Then *_r*
Then * (everything else)

尝试：

SELECT FILE_NAME FROM TABLE
WHERE FILE_NAME LIKE '12345%'
ORDER BY regexp_replace(FILE_NAME, '_m', '_1'),
         regexp_replace(FILE_NAME, '_l', '_2'),
         regexp_replace(FILE_NAME, '_r', '_3')

但这给了我一个错误的结果。

任何有提示的人？

TIA Matt

Answer 1

将您的ORDER BY更改为按数字排序：

 ORDER BY regexp_replace(FILE_NAME, '_m', 1),
          regexp_replace(FILE_NAME, '_l', 2),
          regexp_replace(FILE_NAME, '_r', 3);

e.g。

WITH t
  AS (SELECT '12345_l.tif' AS file_name FROM dual
      UNION
      SELECT '12345_m.tif' FROM dual
      UNION
      SELECT '12345_r.tif' FROM dual
      UNION
      SELECT '12345_x.tif' FROM dual
      UNION
      SELECT '12345_y.tif' FROM dual)
SELECT file_name
  FROM t
 ORDER BY regexp_replace(FILE_NAME, '_m', 1),
          regexp_replace(FILE_NAME, '_l', 2),
          regexp_replace(FILE_NAME, '_r', 3);

给出：

==============
12345_m.tif
12345_l.tif
12345_r.tif
12345_x.tif
12345_y.tif

希望它有所帮助...

或者你可以使用：

 ORDER BY (CASE SUBSTR(file_name, INSTR(file_name, '_')+1, 1)
             WHEN 'm' THEN 1
             WHEN 'l' THEN 2
             WHEN 'r' THEN 3
             ELSE 4
            END) ASC;

E.G：

WITH t
  AS (SELECT '12345_l.tif' AS file_name FROM dual
      UNION
      SELECT '12345_y.tif' FROM dual
      UNION
      SELECT '12345_r.tif' FROM dual
      UNION
      SELECT '12345_x.tif' FROM dual
      UNION
      SELECT '12345_m.tif' FROM dual)
SELECT file_name
  FROM t
 ORDER BY (CASE SUBSTR(file_name, INSTR(file_name, '_')+1, 1)
             WHEN 'm' THEN 1
             WHEN 'l' THEN 2
             WHEN 'r' THEN 3
             ELSE 4
            END) ASC;

给出：

12345_m.tif
12345_l.tif
12345_r.tif
12345_x.tif
12345_y.tif

ORACLE SQL |修改ORDER BY中的数据

1 个答案: