This is how the XSD should be specified

BestMain

<?xml version="1.0" encoding="UTF-8"?>
<xs:schema targetNamespace="http://schemas.asidua.com/CCP/IntegrationServices/2011-11-18/Data" xmlns="http://schemas.asidua.com/CCP/IntegrationServices/2011-11-18/Data" xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:q2="http://microsoft.com/wsdl/types/" elementFormDefault="unqualified" attributeFormDefault="unqualified">
	<xs:import namespace="http://microsoft.com/wsdl/types/" schemaLocation=".\Types.xsd"/>
	<xs:element name="SelectRequest">
		<xs:annotation>
			<xs:documentation>Comment describing your root element</xs:documentation>
		</xs:annotation>
		<xs:complexType>
			<xs:sequence>
				<xs:element name="CriteriaItem" type="AdapterItem"/>
			</xs:sequence>
		</xs:complexType>
	</xs:element>
	<xs:element name="SelectResponse">
		<xs:annotation>
			<xs:documentation>Comment describing your root element</xs:documentation>
		</xs:annotation>
	</xs:element>
	<xs:complexType name="AdapterItem">
		<xs:sequence>
			<xs:element name="Attributes" type="ArrayOfAdapterAttribute" minOccurs="0"/>
			<xs:element name="EntityName" type="xs:string" minOccurs="0"/>
		</xs:sequence>
	</xs:complexType>
	<xs:complexType name="ArrayOfAdapterAttribute">
		<xs:sequence>
			<xs:element name="Attribute" type="AdapterAttribute" nillable="true" minOccurs="0" maxOccurs="unbounded"/>
		</xs:sequence>
	</xs:complexType>
	<xs:complexType name="AdapterAttribute">
		<xs:sequence>
			<xs:element name="Name" type="xs:string" minOccurs="0"/>
			<xs:element name="Value" type="xs:anyType" minOccurs="0"/>
		</xs:sequence>
	</xs:complexType>
	<xs:complexType name="ArrayOfInt">
		<xs:sequence>
			<xs:element name="int" type="xs:int" nillable="true" minOccurs="0" maxOccurs="unbounded"/>
		</xs:sequence>
	</xs:complexType>
	<xs:complexType name="ArrayOfBoolean">
		<xs:sequence>
			<xs:element name="boolean" type="xs:boolean" nillable="true" minOccurs="0" maxOccurs="unbounded"/>
		</xs:sequence>
	</xs:complexType>
	<xs:complexType name="ArrayOfDateTime">
		<xs:sequence>
			<xs:element name="dateTime" type="xs:dateTime" nillable="true" minOccurs="0" maxOccurs="unbounded"/>
		</xs:sequence>
	</xs:complexType>
	<xs:complexType name="ArrayOfGuid">
		<xs:sequence>
			<xs:element name="guid" type="q2:guid" nillable="true" minOccurs="0" maxOccurs="unbounded"/>
		</xs:sequence>
	</xs:complexType>
	<xs:complexType name="ArrayOfDecimal">
		<xs:sequence>
			<xs:element name="decimal" type="xs:decimal" nillable="true" minOccurs="0" maxOccurs="unbounded"/>
		</xs:sequence>
	</xs:complexType>
	<xs:complexType name="ArrayOfDouble">
		<xs:sequence>
			<xs:element name="double" type="xs:double" nillable="true" minOccurs="0" maxOccurs="unbounded"/>
		</xs:sequence>
	</xs:complexType>
	<xs:complexType name="ArrayOfAdapterItem">
		<xs:sequence>
			<xs:element name="AdapterItem" type="AdapterItem" nillable="true" minOccurs="0" maxOccurs="unbounded"/>
		</xs:sequence>
	</xs:complexType>
	<xs:complexType name="ItemReferenceValue">
		<xs:sequence>
			<xs:element name="EntityName" type="xs:string" minOccurs="0"/>
			<xs:element name="ForeignKey" minOccurs="0"/>
			<xs:element name="DisplayNameIfKnown" type="xs:string" minOccurs="0"/>
		</xs:sequence>
	</xs:complexType>
	<xs:complexType name="ArrayOfItemReferenceValue">
		<xs:sequence>
			<xs:element name="ItemReferenceValue" type="ItemReferenceValue" nillable="true" minOccurs="0" maxOccurs="unbounded"/>
		</xs:sequence>
	</xs:complexType>
	<xs:complexType name="ArrayOfString">
		<xs:sequence>
			<xs:element name="string" type="xs:string" nillable="true" minOccurs="0" maxOccurs="unbounded"/>
		</xs:sequence>
	</xs:complexType>
	<xs:complexType name="ArrayOfSchemaAttribute">
		<xs:sequence>
			<xs:element name="SchemaAttribute" type="SchemaAttribute" nillable="true" minOccurs="0" maxOccurs="unbounded"/>
		</xs:sequence>
	</xs:complexType>
	<xs:complexType name="SchemaAttribute">
		<xs:sequence>
			<xs:element name="Name" type="xs:string" minOccurs="0"/>
			<xs:element name="ClrTypeName" type="xs:string" minOccurs="0"/>
			<xs:element name="AdapterItemEntityNames" type="ArrayOfString" minOccurs="0"/>
			<xs:element name="AdapterItemEntityNamesSerializationOptimised" type="ArrayOfString" minOccurs="0"/>
			<xs:element name="Usage" type="AttributeUsage" default="ReadWriteOptional" minOccurs="0"/>
			<xs:element name="PostWorkflowUsage" type="AttributeUsage" default="ReadWriteOptional" minOccurs="0"/>
			<xs:element name="Sensitivity" type="Sensitivity"/>
			<xs:element name="Indexing" type="Indexing"/>
			<xs:element name="Description" type="xs:string" minOccurs="0"/>
		</xs:sequence>
	</xs:complexType>
	<xs:simpleType name="AttributeUsage">
		<xs:list>
			<xs:simpleType>
				<xs:restriction base="xs:string">
					<xs:enumeration value="Default"/>
					<xs:enumeration value="SelectCriteriaOptional"/>
					<xs:enumeration value="SelectCriteriaMandatory"/>
					<xs:enumeration value="SelectResultsOptional"/>
					<xs:enumeration value="SelectResultsMandatory"/>
					<xs:enumeration value="CreateValueOptional"/>
					<xs:enumeration value="CreateValueMandatory"/>
					<xs:enumeration value="CreateResultsOptional"/>
					<xs:enumeration value="CreateResultsMandatory"/>
					<xs:enumeration value="UpdateCriteriaOptional"/>
					<xs:enumeration value="UpdateCriteriaMandatory"/>
					<xs:enumeration value="UpdateValueOptional"/>
					<xs:enumeration value="UpdateValueMandatory"/>
					<xs:enumeration value="UpdateResultsOptional"/>
					<xs:enumeration value="UpdateResultsMandatory"/>
					<xs:enumeration value="DeleteCriteriaOptional"/>
					<xs:enumeration value="DeleteCriteriaMandatory"/>
					<xs:enumeration value="CreateValueAndResultsOptional"/>
					<xs:enumeration value="ReadOnlyOptional"/>
					<xs:enumeration value="ReadOnlyResultsMandatory"/>
					<xs:enumeration value="ReadWriteOptional"/>
					<xs:enumeration value="ReadWriteMandatory"/>
					<xs:enumeration value="WriteOnlyOptional"/>
					<xs:enumeration value="WriteOnlyMandatory"/>
				</xs:restriction>
			</xs:simpleType>
		</xs:list>
	</xs:simpleType>
	<xs:simpleType name="Sensitivity">
		<xs:restriction base="xs:string">
			<xs:enumeration value="None"/>
			<xs:enumeration value="HideFromLogs"/>
		</xs:restriction>
	</xs:simpleType>
	<xs:simpleType name="Indexing">
		<xs:restriction base="xs:string">
			<xs:enumeration value="None"/>
			<xs:enumeration value="PrimaryKey"/>
			<xs:enumeration value="ForeignKey"/>
		</xs:restriction>
	</xs:simpleType>
</xs:schema>