Optionalparts: LegendCubeHostPartsReadonlyapplicationReadonlyconnectionReads the databases behind direct connections (PLAN §6.8); without one, the source picker offers no database connection
ReadonlydataThe deployed data products (PLAN §6.8); without one, the source dialog offers no data products
ReadonlyengineReadonlyengineThe engine URL and compression Cube's engine clients share, which Dev Settings changes
ReadonlyingestThe deployed ingest definitions (PLAN §6.7); without one, the source dialog offers no ingest data sets
ReadonlymodelReadonlyprojectThe published projects in the host's depot (PLAN §6.3); without one, the source dialog offers no projects
ReadonlyserviceThe deployed services (PLAN §6.4), in progress; without one, the source dialog offers no services
A Legend deployment as the host of the Cube page (PLAN §3.5, §11.18): the application's store, the engine and the bundled models, direct database connections read through the engine, the services in its registry, and the deployment's projects, data products and ingest data sets where it has the servers for them. Legend Query and Legend Analytics each build one per visit to the page, from their own config.