Question

我有源表，其中包含有关员工的详细信息，我需要派生一个缺失信息表。列表中缺少值。缺少的值可能是NULL或只是空的空格。

Source Table
**************

Name    Age       Gender     Experience 
-------------------------------------------------------------
David   22         M           IT
John    [NULL]     M          POLITICS
Judy    19      [NULL]        [NULL]
Jasmine [NULL]  [NULL]        [NULL]


Target Table
**************

Name    Missing_description
---------------------------------------------
John    Missing Age
Judy    Missing Gender, Experience
Jasmine Missing Age, Gender, Experience

Answer 1

试

insert into TargetTable (name, description)
select name,'Missing'||description from (
select name, LISTAGG(descr, ', ') within group (order by descr) as description
from (
 select name, 'age,' as descr from SourceTable where age is null
 union all
 select name, 'Gener,' from SourceTable where gender is null
 union all
 select name, 'Experience' from SourceTable where Experience  is null    
) as a
group by name) as b

http://www.oracle-base.com/articles/misc/string-aggregation-techniques.php

Answer 2

通过内存写入，现在没有安装oracle，但查询可以是这样的：

insert into TargetTable (name, description)
select name, LISTAGG(descr, ', ') within group (order by descr) as description
from (
 select name, 'Missing age' as descr from SourceTable where age is null
 union all
 select name, 'Missing Gener' from SourceTable where gender is null
 union all
 ...
) as a
group by name

字符串聚合取自String Aggregation Techniques

发布具有缺失值的列 - oracle

2 个答案: