API Reference > imodeljs-backend > iModels > ChangeSummaryManager > extractChangeSummaries extractChangeSummaries MethodStatic Extracts change summaries from the specified iModel. Change summaries are extracted from the version the iModel was opened with up through the specified start version. If no start version has been specified, the first version will be used. extractChangeSummaries(requestContext: AuthorizedClientRequestContext, iModel: IModelDb, options?: ChangeSummaryExtractOptions): Promise<Id64String[]> throws IModelError if the iModel is standalone Parameter Type Description requestContext AuthorizedClientRequestContext The client request context iModel IModelDb iModel to extract change summaries for. The iModel must not be a standalone iModel.Note: For every version to extract a summary from, the method moves the iModel to that version before extraction. Afterthe extraction has completed, the iModel is moved back to the original version. options ChangeSummaryExtractOptions Extraction options Returns - Promise<Id64String[]> the Ids of the extracted change summaries. Defined in core/backend/src/ChangeSummaryManager.ts Line 145 Last Updated: 13 June, 2024