如何从Oracle数据库中的XML字段中以表格格式提取数据？

Question

I'm trying to extract data in tabular format from an XML field in an Oracle database. Please see sample xml field below:

<?xml version='1.0' encoding='UTF-8'?>
<root>
    <element1>
        <Header Client_ID="100" Sent_date_time="2015-03-02T9:30:43.808-06:00"/>
        <element2>
            <element3 UnitPrice="3.2" ItemID="njh1"/>
            <element3 UnitPrice="4.1" ItemID="ole5"/>
            <element3 UnitPrice="4.6" ItemID="usd3"/>
            <element3 UnitPrice="8.2" ItemID="eor9"/>
            <element3 UnitPrice="2.9" ItemID="abc8"/>
            <element3 UnitPrice="5.1" ItemID="gfd3"/>
            <element3 UnitPrice="4.9" ItemID="kdu0"/>
            <element3 UnitPrice="6.1" ItemID="uso8"/>
        </element2>
    </element1>
</root>

My aim is to query the itemID and UnitPrice fields from the xml field above in the format shown below:

ItemID  UnitPrice
njh1      3.2
ole5      4.1
usd3      4.6
eor9      8.2
abc8      2.9
gfd3      5.1
kdu0      4.9
uso8      6.1

I'm fairly new to querying data from xml fields. I have tried using the getStringVal, but all I get is one single long string. Please advise on a solution. Please note that I don't have dba rights to this database.

Thank you

Answer 1

You have to use XMLTABLE function for this.

SQL Fiddle

Oracle 11g R2 Schema Setup :

create table xml_test(
  xml_col varchar2(2000)
  );

insert into xml_test values(
  '<?xml version=''1.0'' encoding=''UTF-8''?>
<root>
    <element1>
        <Header Client_ID="100" Sent_date_time="2015-03-02T9:30:43.808-06:00"/>
        <element2>
            <element3 UnitPrice="3.2" ItemID="njh1"/>
            <element3 UnitPrice="4.1" ItemID="ole5"/>
            <element3 UnitPrice="4.6" ItemID="usd3"/>
            <element3 UnitPrice="8.2" ItemID="eor9"/>
            <element3 UnitPrice="2.9" ItemID="abc8"/>
            <element3 UnitPrice="5.1" ItemID="gfd3"/>
            <element3 UnitPrice="4.9" ItemID="kdu0"/>
            <element3 UnitPrice="6.1" ItemID="uso8"/>
        </element2>
    </element1>
</root>'
  );

Query :

select cols.ItemID, cols.UnitPrice
from xml_test x,
  xmltable('root/element1/element2/element3'
           passing xmltype(x.xml_col)
           columns ItemID varchar2(10) path '@ItemID',
                   UnitPrice varchar2(10) path '@UnitPrice'
           ) cols;

Results :

| ITEMID | UNITPRICE |
|--------|-----------|
|   njh1 |       3.2 |
|   ole5 |       4.1 |
|   usd3 |       4.6 |
|   eor9 |       8.2 |
|   abc8 |       2.9 |
|   gfd3 |       5.1 |
|   kdu0 |       4.9 |
|   uso8 |       6.1 |