API Reference > imodeljs-backend > Relationships Relationships Classes that describe the relationships between elements. Classes Name Description CategoryOwnsSubCategories Relates a parent Category to SubCategory child elements. DefinitionGroupGroupsDefinitions Relates a DefinitionGroup to its DefinitionElement members. DrawingGraphicRepresentsElement Relates a DrawingGraphic to the Element that it represents ElementDrivesElement A Relationship indicating that one Element drives another Element. Beta ElementEncapsulatesElements Relates a parent Element to child Elements which represent hidden parts of the Entity. ElementGroupsMembers An ElementRefersToElements relationship where one Element groups a set of other Elements. ElementOwnsChildElements Relates a parent Element to child Elements which represent parts of the Entity modeled by the parent Element. ElementOwnsExternalSourceAspects Relates an Element and an ExternalSourceAspect that it owns. ElementOwnsMultiAspects Relates an Element and an ElementMultiAspect that it owns. ElementOwnsUniqueAspect Relates an Element and an ElementUniqueAspect that it owns. ElementRefersToElements A Relationship where one Element refers to another Element ExternalSourceAttachmentAttachesSource Relates an ExternalSource to the RepositoryLink that it is persisted in. Beta ExternalSourceGroupGroupsSources Relates an ExternalSourceGroup to its ExternalSource members. Beta ExternalSourceIsInRepository Relates an ExternalSource to the RepositoryLink that it is persisted in. Beta ExternalSourceOwnsAttachments Relates a parent ExternalSource to its ExternalSourceAttachment children. Beta FolderContainsRepositories Relates a parent FolderLink to its RepositoryLink children. Beta GeometricElement2dHasTypeDefinition Relates a GeometricElement2d to its TypeDefinitionElement GeometricElement3dHasTypeDefinition Relates a GeometricElement3d to its TypeDefinitionElement GraphicalElement2dIsOfType Relates a GraphicalElement2d to its GraphicalType2d GraphicalElement3dRepresentsElement Relates a GraphicalElement3d to the Element that it represents GroupImpartsToMembers Represents group membership where the group Element (and its properties) impart information about the member Elements above mere membership. PhysicalElementAssemblesElements Relates a parent PhysicalElement to PhysicalElement children that it assembles. PhysicalElementIsOfPhysicalMaterial Relates a PhysicalElement to its PhysicalMaterial PhysicalElementIsOfType Relates a PhysicalElement to its PhysicalType PhysicalTypeIsOfPhysicalMaterial Relates a PhysicalType to its PhysicalMaterial Relationship Base class for all link table ECRelationships Relationships Manages Relationships. RenderMaterialOwnsRenderMaterials Relates a parent RenderMaterial to RenderMaterial child elements. SpatialLocationIsOfType Relates a SpatialLocationElement to its SpatialLocationType SubjectOwnsPartitionElements Relates a parent Subject to InformationPartitionElement child elements. SubjectOwnsSubjects Relates a parent Subject to Subject child elements. SynchronizationConfigProcessesSources Relates a SynchronizationConfigLink to N ExternalSource instances. Beta SynchronizationConfigSpecifiesRootSources Relates a SynchronizationConfigLink to root ExternalSource instances. Beta Interfaces Name Description ElementDrivesElementProps Properties that are common to all types of ElementDrivesElements Beta ElementGroupsMembersProps Properties that are common to all types of link table ECRelationships Last Updated: 15 June, 2021