如何在 ORACLE Select 语句中使用条件将单个记录行转换为列

Question

我需要在前面显示列名。基于列中选择语句中满足的条件的列具有我需要的列作为一条记录的值。为此，我正在尝试编写数据库查询。你能帮忙生成这个查询吗

Answer 1

使用附加条件取消透视；第 1 - 4 行代表样本数据（您有，因此您的查询从第 5 行开始）：

SQL> with test (id, emp_name, is_maths_passed, is_science_passed, is_social_passed) as
  2    (select 123, 'Robert', 'YES', 'NO' , 'YES' from dual union all
  3     select 345, 'Devid' , 'NO' , 'YES', 'YES' from dual
  4    )
  5  select code, passed
  6  from (select * from (select * from test where id = &par_id)
  7        unpivot (passed
  8                 for code
  9                 in (is_maths_passed   as 'is_maths_passed',
 10                     is_science_passed as 'is_science_passed',
 11                     is_social_passed  as 'is_social_passed'
 12                    )
 13                )
 14       )
 15  where passed = 'YES';
Enter value for par_id: 123

CODE              PAS
----------------- ---
is_maths_passed   YES
is_social_passed  YES

SQL> /
Enter value for par_id: 345

CODE              PAS
----------------- ---
is_science_passed YES
is_social_passed  YES

SQL>