问题描述
我试图透视一个表，根据行动态创建列。
我正在使用子句PIVOT XML，但是我没有将XML列解析为列。
我的桌子看起来像这样：
我想要这样：
解决方法
Pivot xml返回XMLType，但是您显示了标准表结构。
枢轴xml的示例：
with t(id,dt,medical_test,positive) as (
select 1,date'2020-04-20','blood count',1 from dual union all
select 2,date'2020-04-26','bone marrow aspiration',date'2020-04-30','cephalin-cholesterol flocculation',0 from dual union all
select 2,date'2020-05-05','hematocrit',0 from dual union all
select 3,date'2020-04-02','lumbar puncture',date'2020-04-13','Pap smear',1 from dual union all
select 4,date'2020-06-06',1 from dual
)
select *
from t
pivot xml(
max(positive) as positive
for medical_test in (any)
);
结果：
ID DT MEDICAL_TEST_XML
---------- ------------------- ------------------------------------------------------------------------------------
1 2020-04-20 00:00:00 <PivotSet><item><column name = "MEDICAL_TEST">blood count</column><column name = "POSITIVE">1</column></item></PivotSet>
2 2020-04-26 00:00:00 <PivotSet><item><column name = "MEDICAL_TEST">bone marrow aspiration</column><column name = "POSITIVE">1</column></item></PivotSet>
2 2020-04-30 00:00:00 <PivotSet><item><column name = "MEDICAL_TEST">cephalin-cholesterol flocculation</column><column name = "POSITIVE">0</column></item></PivotSet>
2 2020-05-05 00:00:00 <PivotSet><item><column name = "MEDICAL_TEST">hematocrit</column><column name = "POSITIVE">0</column></item></PivotSet>
3 2020-04-02 00:00:00 <PivotSet><item><column name = "MEDICAL_TEST">lumbar puncture</column><column name = "POSITIVE">0</column></item></PivotSet>
3 2020-04-13 00:00:00 <PivotSet><item><column name = "MEDICAL_TEST">Pap smear</column><column name = "POSITIVE">1</column></item></PivotSet>
4 2020-06-06 00:00:00 <PivotSet><item><column name = "MEDICAL_TEST">cephalin-cholesterol flocculation</column><column name = "POSITIVE">1</column></item></PivotSet>
使用简单的PIVOT可以轻松实现您想要的目标：
with t(id,1 from dual
)
select--+ no_merge
piv.*
from t
pivot (
max(positive)
for medical_test in (
'blood count','Pap smear'
)
) piv
order by 1,2;
结果：
ID DT 'blood count' 'bone marrow aspiration' 'cephalin-cholesterol flocculation' 'hematocrit' 'lumbar puncture' 'Pap smear'
---------- ------------------- ------------- ------------------------ ----------------------------------- ------------ ----------------- -----------
1 2020-04-20 00:00:00 1
2 2020-04-26 00:00:00 1
2 2020-04-30 00:00:00 0
2 2020-05-05 00:00:00 0
3 2020-04-02 00:00:00 0
3 2020-04-13 00:00:00 1
4 2020-06-06 00:00:00 1