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  <xsd:element id="dh_WeightedAverageRemainingLeaseTermAbstract" name="WeightedAverageRemainingLeaseTermAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dh_AccruedExpensesAndOtherCurrentLiabilities" name="AccruedExpensesAndOtherCurrentLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dh_AccruedExpensesContingentConsiderationCurrent" name="AccruedExpensesContingentConsiderationCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dh_AcquisitionOfLimitedLiabilityCompanyLlc" name="AcquisitionOfLimitedLiabilityCompanyLlc" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dh_Additionalleasetermperiod" name="Additionalleasetermperiod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dh_AmountExpectedPaidOverNextTwelveMonths" name="AmountExpectedPaidOverNextTwelveMonths" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dh_AssetAcquisitionConsiderationTransferredInitialCashInvestment" name="AssetAcquisitionConsiderationTransferredInitialCashInvestment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dh_BenefitFromRemainingOfAnyTaxBenefits" name="BenefitFromRemainingOfAnyTaxBenefits" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dh_BusinessCombinationContingentConsiderationEarnoutPayment" name="BusinessCombinationContingentConsiderationEarnoutPayment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dh_BusinessCombinationContingentConsiderationLiabilityOther" name="BusinessCombinationContingentConsiderationLiabilityOther" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dh_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeaseRightOfUseAssets" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeaseRightOfUseAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dh_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeaseRightOfUseLiability" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeaseRightOfUseLiability" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dh_CapitalizedFinancingCosts" name="CapitalizedFinancingCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dh_CapitalUnitsAuthorizedIssuedAndOutstanding" name="CapitalUnitsAuthorizedIssuedAndOutstanding" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="dh_CapitalUnitsIssued" name="CapitalUnitsIssued" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="dh_ChangesInContingentConsideration" name="ChangesInContingentConsideration" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dh_ComprehensiveIncomeLossAttributableToDefinitiveOpcoPriorToReorganizationTransactions" name="ComprehensiveIncomeLossAttributableToDefinitiveOpcoPriorToReorganizationTransactions" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dh_ComprehensiveIncomeNetOfTaxIncludingNonControllingInterests" name="ComprehensiveIncomeNetOfTaxIncludingNonControllingInterests" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dh_DeferredContractCosts" name="DeferredContractCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <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_DeferredTaxLiabilityDueToAcquisition" name="DeferredTaxLiabilityDueToAcquisition" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dh_EffectOfLlcUnitExchanges" name="EffectOfLlcUnitExchanges" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dh_EffectOfLlcUnitExchangeShares" name="EffectOfLlcUnitExchangeShares" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dh_EquityInvestment" name="EquityInvestment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dh_FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationNetChangeInFairValueAndOtherAdjustments" name="FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationNetChangeInFairValueAndOtherAdjustments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dh_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFour" name="FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFour" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dh_ForfeitedUnvestedIncentiveUnits" name="ForfeitedUnvestedIncentiveUnits" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dh_GainLossInAccumulatedOtherComprehensiveIncome" name="GainLossInAccumulatedOtherComprehensiveIncome" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" 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_IntangibleAssetsIncludingGoodwillAccumulatedAmortization" name="IntangibleAssetsIncludingGoodwillAccumulatedAmortization" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <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_LongTermDeferredContractCosts" name="LongTermDeferredContractCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dh_NetLossAttributableToParentPriorToTheReorganizationTransactions" name="NetLossAttributableToParentPriorToTheReorganizationTransactions" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dh_Operatingleasecommencementdate" name="Operatingleasecommencementdate" type="xbrli:dateItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dh_PaymentForDistributionsToMembers" name="PaymentForDistributionsToMembers" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dh_PercentageOfOwnership" name="PercentageOfOwnership" type="xbrli:pureItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" 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_PreIpoOwnersAmountCashSavings" name="PreIpoOwnersAmountCashSavings" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dh_PurchaseOfLimitedLiabilityCompanyLlcUnit" name="PurchaseOfLimitedLiabilityCompanyLlcUnit" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dh_PurchaseOptionOwnershipPercentage" name="PurchaseOptionOwnershipPercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="dh_RecoveryOfProvisionForDoubtfulAccountsReceivable" name="RecoveryOfProvisionForDoubtfulAccountsReceivable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dh_RepaymentOfLongTermDebtFromIpoProceeds" name="RepaymentOfLongTermDebtFromIpoProceeds" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dh_RevenueRemainingPerformanceObligationCurrent" name="RevenueRemainingPerformanceObligationCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" 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_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsEffectOfReorganizationTransactionsAndIpo" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsEffectOfReorganizationTransactionsAndIpo" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dh_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageEffectOfReorganizationTransactionsAndIpo" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageEffectOfReorganizationTransactionsAndIpo" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dh_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAveragePerformanceBasedUnitsExchangedForTimeBasedUnitsDateFairValue" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAveragePerformanceBasedUnitsExchangedForTimeBasedUnitsDateFairValue" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dh_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPerformanceBasedUnitsExchangedForTimeBasedUnits" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPerformanceBasedUnitsExchangedForTimeBasedUnits" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dh_ShareBasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedNumberOfSharesParticipationThresholdAfterModification" name="ShareBasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedNumberOfSharesParticipationThresholdAfterModification" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dh_ShareBasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedNumberOfSharesParticipationThresholdAfterModification" name="ShareBasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedNumberOfSharesParticipationThresholdAfterModification" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <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_TaxReceivableAgreementLiability" name="TaxReceivableAgreementLiability" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dh_TaxReceivableAgreementRealizedTaxBenefitsPayableToRelatedParties" name="TaxReceivableAgreementRealizedTaxBenefitsPayableToRelatedParties" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dh_TaxReceivableAgreementRealizedTaxBenefitsPayableToRelatedPartiesPercent" name="TaxReceivableAgreementRealizedTaxBenefitsPayableToRelatedPartiesPercent" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <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_TaxReceivableAgreementsLiabilityNetOfCurrentPortion" name="TaxReceivableAgreementsLiabilityNetOfCurrentPortion" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dh_TransactionExpenses" name="TransactionExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dh_UnamortizedFinancingCosts" name="UnamortizedFinancingCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dh_VestedIncentiveUnits" name="VestedIncentiveUnits" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <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_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetailsLineItems" name="DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetailsLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dh_AnalyticalWizardsAcquisitionMember" name="AnalyticalWizardsAcquisitionMember" 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_BankOfAmericaNAMember" name="BankOfAmericaNAMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dh_ClassBProfitInterestUnitsMember" name="ClassBProfitInterestUnitsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_ContingentConsiderationMember" name="ContingentConsiderationMember" 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_DefinitiveHealthcareCorpMember" name="DefinitiveHealthcareCorpMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dh_DefinitiveOpcoMember" name="DefinitiveOpcoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dh_DirectedShareProgramMember" name="DirectedShareProgramMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dh_FollowOnOfferingMember" name="FollowOnOfferingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dh_GoldmanSachsBankUsaMember" name="GoldmanSachsBankUsaMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_MonoclAcquisitionMember" name="MonoclAcquisitionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dh_OfficeSpaceAndDataCenterFacilitiesMember" name="OfficeSpaceAndDataCenterFacilitiesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dh_PaidInKindInterestOnTwoThousandNineteenTermLoanMember" name="PaidInKindInterestOnTwoThousandNineteenTermLoanMember" 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_PerformanceBasedMember" name="PerformanceBasedMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dh_PerformanceBasedRsusMember" name="PerformanceBasedRsusMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dh_PlatformSubscriptionsMember" name="PlatformSubscriptionsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dh_ProductDevelopmentMember" name="ProductDevelopmentMember" type="dtr-types:domainItemType" 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_PurchaseOptionMember" name="PurchaseOptionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dh_ReorganizationTransactionsMember" name="ReorganizationTransactionsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dh_RichardBoothMember" name="RichardBoothMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dh_SamuelAHamoodMember" name="SamuelAHamoodMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dh_TimeBasedMember" name="TimeBasedMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dh_TimeBasedRsusMember" name="TimeBasedRsusMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_TwoThousandNineteenEquityIncentivePlanMember" name="TwoThousandNineteenEquityIncentivePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dh_TwoThousandNineteenRevolvingLineOfCreditMember" name="TwoThousandNineteenRevolvingLineOfCreditMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_TwoThousandTwentyOneEquityIncentivePlanMember" name="TwoThousandTwentyOneEquityIncentivePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dh_TwoThousandTwentyOneRevolvingLineOfCreditMember" name="TwoThousandTwentyOneRevolvingLineOfCreditMember" 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_VestedAndUnvestedUnitsMember" name="VestedAndUnvestedUnitsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dh_AccountingPoliciesTable" name="AccountingPoliciesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dh_SummaryOfAllocationOfPurchasePriceToTheFairValueOfAssetsAcquiredTableTextBlock" name="SummaryOfAllocationOfPurchasePriceToTheFairValueOfAssetsAcquiredTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <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_ScheduleOfLeasesTermAndDiscountRateTableTextBlock" name="ScheduleOfLeasesTermAndDiscountRateTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
</xsd:schema>
