努力从XML数据中提取值（T-SQL）

像这样的演示：

declare @x XML='<EncounterValidationResponse xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://www.dhcs.ca.gov/EDS/DHCSResponse" ResponseVersion="1.2">
  <EncounterFileName>EncounterFileName</EncounterFileName>
  <EncounterSubmitterName>EncounterSubmitter</EncounterSubmitterName>
  <EncounterSubmissionDate>2019-12-13T08:47:00.0000000-08:00</EncounterSubmissionDate>
  <ValidationStatus>Accepted</ValidationStatus>
  <Transactions>
    <Transaction>
      <IdentifierName>BatchNumber</IdentifierName>
      <TransactionNumber>1277104</TransactionNumber>
      <Identifiers>
        <Envelope IdentifierName="OriginatorTransactionId" IdentifierValue="1277104-00" />
      </Identifiers>
      <Encounters>
        <Encounter Status="Accepted">
          <IdentifierType>TransactionIdentifier</IdentifierType>
          <EncounterReferenceNumber>8129339999264</EncounterReferenceNumber>
          <EncounterId>1934049991539</EncounterId>
          <EncounterResponses>
            <Response Severity="Warning">
              <Id>0x0006D</Id>
              <Description>MEDS indicates multiple records exist for this beneficiary</Description>
            </Response>
            <Response Severity="Warning">
              <Id>0x00221</Id>
              <Description>Prescriber Taxonomy (296)  is either not provided or is invalid</Description>
            </Response>
            <Response Severity="Warning">
              <Id>0x00249</Id>
              <Description>Reason for Service Code (439-E4) is requested per the payer sheet but no value is provided/specified.</Description>
            </Response>
            <Response Severity="Warning">
              <Id>0x00249</Id>
              <Description>Professional Service Code (440-E5) is requested per the payer sheet but no value is provided/specified.</Description>
            </Response>
            <Response Severity="Warning">
              <Id>0x00249</Id>
              <Description>Result of Service Code (441-E6) is requested per the payer sheet but no value is provided/specified.</Description>
            </Response>
          </EncounterResponses>
        </Encounter>
      </Encounters>
    </Transaction>
  </Transactions>
</EncounterValidationResponse>';


with xmlnamespaces (DEFAULT 'http://www.dhcs.ca.gov/EDS/DHCSResponse') 
select  t.n.value('@Status','nvarchar(100)') status,
     t.n.value('EncounterReferenceNumber[1]','nvarchar(100)') EncounterReferenceNumber,
     r.n.value('@Severity','nvarchar(100)') Severity,
     r.n.value('Id[1]','nvarchar(100)') Id,
     r.n.value('Description[1]','nvarchar(100)') Description
from @x.nodes('/EncounterValidationResponse/Transactions/Transaction/Encounters/Encounter') t(n)
cross apply t.n.nodes('EncounterResponses/Response') r(n);