API Reference > presentation-common > PresentationRules > RelatedInstanceSpecificationNew > isRequired isRequired isRequired: undefined | boolean Is the related instance required to exist. If yes, primary instance won't be returned if the related instance doesn't exist. If not, primary instance will be returned, but related instance will be null. In SQL terms in can be compared to INNER JOIN vs OUTER JOIN. Defined in presentation/common/src/rules/RelatedInstanceSpecification.ts Line 132 Last Updated: 13 June, 2024