在oracle中将列结果转换为多行[重复]

Question

我在 oracle db 中有 material_info 表

MATERIAL    COUNTRIES
----------------------------
HX345TY     US,IN,SG,CN,JP
MXT15WO     SL,AU,IN,US,AF
UIY7890#RT  UK,US,IN,SG,PK

我想要如下输出

MATERIAL    COUNTRIES
-----------------------------
HX345TY     US
HX345TY     IN
HX345TY     SG
HX345TY     CN
HX345TY     JP
MXT15WO     SL
MXT15WO     AU
MXT15WO     IN
MXT15WO     US
MXT15WO     AF
UIY7890#RT  UK
UIY7890#RT  US
UIY7890#RT  IN
UIY7890#RT  SG
UIY7890#RT  PK

我为此编写了如下查询。但它不工作。谁能给出解决方案

select material, trim(regexp_substr(COUNTRIES,'[^,]+', 1, level) ) COUNTRIES, level
from material_info connect by regexp_substr(COUNTRIES, '[^,]+', 1, level) is not null;

Answer 1

您可以通过使用distinct 和regexp_count 进行轻微更改以使其动态

select distinct material,
       regexp_substr(countries, '[^,]+', 1, level) countries
  from material_info
connect by level <= regexp_count(countries, '[^,]+')
order by material;

或使用group by material, countries, level作为

select material,
       regexp_substr(countries, '[^,]+', 1, level) countries
  from material_info
connect by level <= regexp_count(countries, '[^,]+')
group by material, countries, level;

甚至不用trim

Demo

Answer 2

您应该更喜欢prior + sys_guid 技术。对于大量记录，它比 distinct 高效得多。

select material,
       regexp_substr(countries, '[^,]+', 1, level) countries
  from material_info
connect by level <= regexp_count(countries, '[^,]+')
and prior material = material
and prior sys_guid() is not null;

DEMO