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  <xsd:element id="dh_TaxReceivableAgreementRemeasurement" name="TaxReceivableAgreementRemeasurement" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dh_RestructuringplanMember" name="RestructuringplanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dh_TraRemeasurementGain" name="TraRemeasurementGain" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dh_InitialCashInvestmentInPriorYear" name="InitialCashInvestmentInPriorYear" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dh_DeferredTaxLiabilityDueToAcquisition" name="DeferredTaxLiabilityDueToAcquisition" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dh_MembersEquityMember" name="MembersEquityMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dh_CashPaidForAmountsIncludedInTheMeasurementOfLeaseLiabilitiesAbstract" name="CashPaidForAmountsIncludedInTheMeasurementOfLeaseLiabilitiesAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dh_WeightedAverageRemainingLeaseTermAbstract" name="WeightedAverageRemainingLeaseTermAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dh_ProfessionalServicesMember" name="ProfessionalServicesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dh_MonoclAcquisitionMember" name="MonoclAcquisitionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dh_SummaryOfTransactionTransferredTableTextBlock" name="SummaryOfTransactionTransferredTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dh_LimitedLiabilityCompanyLlcMembersEquityUnitBasedCompensationAndStockCompensation" name="LimitedLiabilityCompanyLlcMembersEquityUnitBasedCompensationAndStockCompensation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dh_RevenueRemainingPerformanceObligationNonCurrent" name="RevenueRemainingPerformanceObligationNonCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dh_ConstructionAndSoftwareDevelopmentInProcessMember" name="ConstructionAndSoftwareDevelopmentInProcessMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dh_PaidinkindinterestontwothousandtwentyonetermloanMember" name="PaidinkindinterestontwothousandtwentyonetermloanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dh_DeferredContractCostsMember" name="DeferredContractCostsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dh_PercentageOfOwnership" name="PercentageOfOwnership" type="xbrli:pureItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="dh_GoodwillAndIntangibleAssetsMember" name="GoodwillAndIntangibleAssetsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dh_TwoThousandTwentyOneTermLoanMember" name="TwoThousandTwentyOneTermLoanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dh_VestedIncentiveUnitsValue" name="VestedIncentiveUnitsValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dh_ComputersAndSoftwareMember" name="ComputersAndSoftwareMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dh_AwAcquisitionMember" name="AwAcquisitionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dh_AgencyBondsMember" name="AgencyBondsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dh_StockIssuedDuringPeriodCommonStockUponVestingOfRestrictedStockUnit" name="StockIssuedDuringPeriodCommonStockUponVestingOfRestrictedStockUnit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dh_TaxReceivableAgreementsLiabilityNetOfCurrentPortion" name="TaxReceivableAgreementsLiabilityNetOfCurrentPortion" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dh_DeferredContractCostsNetOfCurrentPortion" name="DeferredContractCostsNetOfCurrentPortion" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dh_TwoThousandNineteenTermLoanMember" name="TwoThousandNineteenTermLoanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dh_IntangibleAssetsIncludingGoodwillGross" name="IntangibleAssetsIncludingGoodwillGross" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dh_TransactionIntegrationAndRestructuringExpenses" name="TransactionIntegrationAndRestructuringExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dh_TaxReceivableAgreementBenefitPercentage" name="TaxReceivableAgreementBenefitPercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dh_PotentialEarnOutPayments" name="PotentialEarnOutPayments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dh_IssuanceOfCommonStockShares" name="IssuanceOfCommonStockShares" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="dh_TwoThousandNineteenDelayedDrawTermLoanMember" name="TwoThousandNineteenDelayedDrawTermLoanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dh_AcquisitionOfLimitedLiabilityCompanyLlc" name="AcquisitionOfLimitedLiabilityCompanyLlc" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dh_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeaseRightOfUseLiability" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeaseRightOfUseLiability" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
</xsd:schema>
