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  <xs:element id="oke_SellorMember" abstract="true" name="SellorMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
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  <xs:element id="oke_DerivativeNotionalAmountNewContracts" abstract="false" name="DerivativeNotionalAmountNewContracts" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
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  <xs:element id="oke_OtherMember" abstract="true" name="OtherMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
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  <xs:element id="oke_TransactionTypeDomain" abstract="true" name="TransactionTypeDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
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  <xs:element id="oke_IndebtednessToAdjustedEbitdaCurrent" abstract="false" name="IndebtednessToAdjustedEbitdaCurrent" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
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  <xs:element id="oke_CommodityExchangesAndImbalances" abstract="false" name="CommodityExchangesAndImbalances" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="oke_ContractwithCustomerLiabilityNetAdditions" abstract="false" name="ContractwithCustomerLiabilityNetAdditions" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
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  <xs:element id="oke_BusinessInterruptionSettlementProceedsReceivedIn2023Member" abstract="true" name="BusinessInterruptionSettlementProceedsReceivedIn2023Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
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  <xs:element id="oke_TransportationandStorageRevenueMember" abstract="true" name="TransportationandStorageRevenueMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="oke_NaturalGasLiquidsDomain" abstract="true" name="NaturalGasLiquidsDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="oke_ScheduleofAccumulatedOtherComprehensiveIncomeLossforRiskManagementAssetsLiabilitiesTableTextBlock" abstract="false" name="ScheduleofAccumulatedOtherComprehensiveIncomeLossforRiskManagementAssetsLiabilitiesTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:textBlockItemType"/>
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  <xs:element id="oke_NaturalGasGatheringandProcessingIntersegmentMember" abstract="true" name="NaturalGasGatheringandProcessingIntersegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
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  <xs:element id="oke_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherDeferredCreditsAndLiabilities" abstract="false" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherDeferredCreditsAndLiabilities" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="oke_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInvestmentsInUnconsolidatedAffiliates" abstract="false" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInvestmentsInUnconsolidatedAffiliates" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
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  <xs:element id="oke_NumberOfMarineTerminals" abstract="false" name="NumberOfMarineTerminals" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
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  <xs:element id="oke_DerivativeNotionalAmountSettled" abstract="false" name="DerivativeNotionalAmountSettled" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
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  <xs:element id="oke_RevenueRemainingPerformanceObligationDomain" abstract="true" name="RevenueRemainingPerformanceObligationDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
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  <xs:element id="oke_BasicEPSfromContinuingOperationsAbstract" abstract="true" name="BasicEPSfromContinuingOperationsAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="oke_NaturalGasLiquidsAxis" abstract="true" name="NaturalGasLiquidsAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
</xs:schema>
