需要读取多个节点的值：ORA-19025: EXTRACTVALUE returns 只有一个节点的值

Question

我可以成功读取 xml 文件：DataTransfer_HH_TWWholesale_001_004_12142020113003.xml 只有一个节点。

但是当我试图从 xml 文件中读取多个节点时：DataTransfer_HH_TWWholesale_001_009_09282020103349.xml，我得到错误ORA-19025: EXTRACTVALUE returns 只有一个节点的值。

如何从多个节点读取值？

下面是我的文件和代码：

文件：DataTransfer_HH_TWWholesale_001_004_12142020113003.xml

<MeterReadsReplyMessage xmlns="http://www.emeter.com/energyip/amiinterface">
<Header>
    <verb>create</verb>
    <noun>DTSMeterReads</noun>
    <revision>2</revision>
    <source>EIP</source>
</Header>
<payload>
        <MeterReading>
            <ServiceDeliveryPoint>
                <mRID>901291331_0001</mRID>
                <idType>SDP_X_UDC_ASSET_ID</idType>
            </ServiceDeliveryPoint>
            <Meter>
                <mRID>SIE_640 C_310149563</mRID>
                <idType>METER_X_UDC_ASSET_ID</idType>
            </Meter>
            <IntervalBlock>
                <readingTypeId>LREG</readingTypeId>
                <ReadingType>
                    <measurementType>Register</measurementType>
                    <touBinNumber>0</touBinNumber>
                    <unit>L</unit>
                    <channelNumber>1</channelNumber>
                    <direction>Delivered</direction>
                </ReadingType>
                <IReading>
                    <endTime>2020-10-08T00:00:00.000Z</endTime>
                    <value>0.0</value>
                    <quality>
                        <validationStatus>EST</validationStatus>
                        <locked>false</locked>
                    </quality>
                </IReading>
            </IntervalBlock>
        </MeterReading>

</payload>
</MeterReadsReplyMessage>

代码：

SELECT EXTRACTVALUE (VALUE (a1),'/Header/verb','xmlns="http://www.emeter.com/energyip/amiinterface')verb,
       EXTRACTVALUE (VALUE (a1),'/Header/noun','xmlns="http://www.emeter.com/energyip/amiinterface')noun,
       EXTRACTVALUE (VALUE (a1),'/Header/source','xmlns="http://www.emeter.com/energyip/amiinterface')source
      FROM xml_tab,TABLE (XMLSEQUENCE (EXTRACT (xml_data,
                                           '/MeterReadsReplyMessage/Header',
                                           'xmlns="http://www.emeter.com/energyip/amiinterface"'
                                           ))) a1
 WHERE file_name = 'DataTransfer_HH_TWWholesale_001_004_12142020113003.xml';

查询：文件：DataTransfer_HH_TWWholesale_001_009_09282020103349.xml

<MeterReadsReplyMessage xmlns="http://www.emeter.com/energyip/amiinterface">
<Header>
    <verb>create</verb>
    <noun>DTSMeterReads</noun>
    <revision>2</revision>
    <source>EIP</source>
</Header>
<payload>
        <MeterReading>
            <ServiceDeliveryPoint>
                <mRID>901291331_0001</mRID>
                <idType>SDP_X_UDC_ASSET_ID</idType>
            </ServiceDeliveryPoint>
            <Meter>
                <mRID>SIE_640 C_310149563</mRID>
                <idType>METER_X_UDC_ASSET_ID</idType>
            </Meter>
            <IntervalBlock>
                <readingTypeId>LREG</readingTypeId>
                <ReadingType>
                    <measurementType>Register</measurementType>
                    <touBinNumber>0</touBinNumber>
                    <unit>L</unit>
                    <channelNumber>1</channelNumber>
                    <direction>Delivered</direction>
                </ReadingType>
                <IReading>
                    <endTime>2020-10-08T00:00:00.000Z</endTime>
                    <value>0.0</value>
                    <quality>
                        <validationStatus>EST</validationStatus>
                        <locked>false</locked>
                    </quality>
                </IReading>
            </IntervalBlock>
        </MeterReading>
        <MeterReading>
            <ServiceDeliveryPoint>
                <mRID>112448526_0001</mRID>
                <idType>SDP_X_UDC_ASSET_ID</idType>
            </ServiceDeliveryPoint>
            <Meter>
                <mRID>SCE_640 Concentric_310037947</mRID>
                <idType>METER_X_UDC_ASSET_ID</idType>
            </Meter>
            <IntervalBlock>
                <readingTypeId>LREG</readingTypeId>
                <ReadingType>
                    <measurementType>Register</measurementType>
                    <touBinNumber>0</touBinNumber>
                    <unit>L</unit>
                    <channelNumber>1</channelNumber>
                    <direction>Delivered</direction>
                </ReadingType>
                <IReading>
                    <endTime>2015-12-21T01:00:00.000Z</endTime>
                    <value>0.0</value>
                    <flags>0</flags>
                    <quality>
                        <validationStatus>VAL</validationStatus>
                        <locked>false</locked>
                    </quality>
                </IReading>
            </IntervalBlock>
        </MeterReading>
        
</payload>
</MeterReadsReplyMessage>

查询：

感谢阅读我的问题。

预期结果：

mRID             mfg_serial_num               readingTypeId   measurementType   Read_time
901291331_0001  SIE_640 C_310149563           LREG             Register         2020-10-08T00:00:00.000Z
112448526_0001  SCE_640 Concentric_310037947  LREG             Register         2015-12-21T01:00:00.000Z

Answer 1

EXTRACT and EXTRACTVALUE XML 函数已弃用。使用 XMLTABLE 代替：

SELECT t.file_name,
       x.*
FROM   xml_tab t
       CROSS APPLY XMLTABLE(
         XMLNAMESPACES( DEFAULT 'http://www.emeter.com/energyip/amiinterface' ),
         '/MeterReadsReplyMessage/payload/MeterReading'
         PASSING t.xml_data
         COLUMNS
           mRID             VARCHAR2(20)  PATH './ServiceDeliveryPoint/mRID',
           mfg_serial_num   VARCHAR2(20)  PATH './Meter/mRID',
           readingTypeID    VARCHAR2(10)  PATH './IntervalBlock/readingTypeId',
           measurement_type VARCHAR2(10)  PATH './IntervalBlock/ReadingType/measurementType',
           reading_time     TIMESTAMP WITH TIME ZONE PATH '//IReading/endTime'
       ) x;

其中，对于您的示例数据：

CREATE TABLE xml_tab ( file_name, xml_data ) AS
SELECT 'DataTransfer_HH_TWWholesale_001_004_12142020113003.xml',
XMLTYPE(
  '<MeterReadsReplyMessage xmlns="http://www.emeter.com/energyip/amiinterface">
<Header>
    <verb>create</verb>
    <noun>DTSMeterReads</noun>
    <revision>2</revision>
    <source>EIP</source>
</Header>
<payload>
        <MeterReading>
            <ServiceDeliveryPoint>
                <mRID>901291331_0001</mRID>
                <idType>SDP_X_UDC_ASSET_ID</idType>
            </ServiceDeliveryPoint>
            <Meter>
                <mRID>SIE_640 C_310149563</mRID>
                <idType>METER_X_UDC_ASSET_ID</idType>
            </Meter>
            <IntervalBlock>
                <readingTypeId>LREG</readingTypeId>
                <ReadingType>
                    <measurementType>Register</measurementType>
                    <touBinNumber>0</touBinNumber>
                    <unit>L</unit>
                    <channelNumber>1</channelNumber>
                    <direction>Delivered</direction>
                </ReadingType>
                <IReading>
                    <endTime>2020-10-08T00:00:00.000Z</endTime>
                    <value>0.0</value>
                    <quality>
                        <validationStatus>EST</validationStatus>
                        <locked>false</locked>
                    </quality>
                </IReading>
            </IntervalBlock>
        </MeterReading>

</payload>
</MeterReadsReplyMessage>'
) FROM DUAL UNION ALL
SELECT 'DataTransfer_HH_TWWholesale_001_009_00000000000000.xml',
       XMLType( '<MeterReadsReplyMessage xmlns="http://www.emeter.com/energyip/amiinterface">
<Header>
    <verb>create</verb>
    <noun>DTSMeterReads</noun>
    <revision>2</revision>
    <source>EIP</source>
</Header>
<payload>
        <MeterReading>
            <ServiceDeliveryPoint>
                <mRID>901291331_0001</mRID>
                <idType>SDP_X_UDC_ASSET_ID</idType>
            </ServiceDeliveryPoint>
            <Meter>
                <mRID>SIE_640 C_310149563</mRID>
                <idType>METER_X_UDC_ASSET_ID</idType>
            </Meter>
            <IntervalBlock>
                <readingTypeId>LREG</readingTypeId>
                <ReadingType>
                    <measurementType>Register</measurementType>
                    <touBinNumber>0</touBinNumber>
                    <unit>L</unit>
                    <channelNumber>1</channelNumber>
                    <direction>Delivered</direction>
                </ReadingType>
                <IReading>
                    <endTime>2020-10-08T00:00:00.000Z</endTime>
                    <value>0.0</value>
                    <quality>
                        <validationStatus>EST</validationStatus>
                        <locked>false</locked>
                    </quality>
                </IReading>
            </IntervalBlock>
        </MeterReading>
        <MeterReading>
            <ServiceDeliveryPoint>
                <mRID>112448526_0001</mRID>
                <idType>SDP_X_UDC_ASSET_ID</idType>
            </ServiceDeliveryPoint>
            <Meter>
                <mRID>SCE_640 Concentric_310037947</mRID>
                <idType>METER_X_UDC_ASSET_ID</idType>
            </Meter>
            <IntervalBlock>
                <readingTypeId>LREG</readingTypeId>
                <ReadingType>
                    <measurementType>Register</measurementType>
                    <touBinNumber>0</touBinNumber>
                    <unit>L</unit>
                    <channelNumber>1</channelNumber>
                    <direction>Delivered</direction>
                </ReadingType>
                <IReading>
                    <endTime>2015-12-21T01:00:00.000Z</endTime>
                    <value>0.0</value>
                    <flags>0</flags>
                    <quality>
                        <validationStatus>VAL</validationStatus>
                        <locked>false</locked>
                    </quality>
                </IReading>
            </IntervalBlock>
        </MeterReading>
        
</payload>
</MeterReadsReplyMessage>'
) FROM DUAL;

输出：

FILE_NAME                                              | MRID           | MFG_SERIAL_NUM       | READINGTYPEID | MEASUREMENT_TYPE | READING_TIME                       
:----------------------------------------------------- | :------------- | :------------------- | :------------ | :--------------- | :----------------------------------
DataTransfer_HH_TWWholesale_001_004_12142020113003.xml | 901291331_0001 | SIE_640 C_310149563  | LREG          | Register         | 2020-10-08T00:00:00.000000000+00:00
DataTransfer_HH_TWWholesale_001_009_00000000000000.xml | 901291331_0001 | SIE_640 C_310149563  | LREG          | Register         | 2020-10-08T00:00:00.000000000+00:00
DataTransfer_HH_TWWholesale_001_009_00000000000000.xml | 112448526_0001 | SCE_640 Concentric_3 | LREG          | Register         | 2015-12-21T01:00:00.000000000+00:00

db<>fiddle here

需要读取多个节点的值：ORA-19025: EXTRACTVALUE returns 只有一个节点的值

Need to read value of multiple node: ORA-19025: EXTRACTVALUE returns value of only one node

oracle12c

xmltable