JDBC objects are sourced from relational databases and so already have primary/foreign key relations defined. In Qlik Data Catalyst, through discovery and ingest, information about these relationships is fetched and retained as part of the source/entity/field metadata. For JDBC sources, users can drill into Field Information to see which fields are primary "Key" fields and which are "Foreign Key" fields. Note that while relations are fetched for both internal (Discover) and external (Source) objects, Discover Field Information does not display the Key/Foreign Key Details in "Field Information: General Information" tab (though the Lineage tab captures the relationship in both Discover/Source).
The following example illustrates how primary Key and Foreign Key fields are identified for an Entity called "pd_field" that exists in podium_core metadata tables.
Persisted relations are informative for creation of dataflows in Prepare.
Once the entity or entities have been added to the canvas, SAVE the dataflow, select RECOMMENDATIONS to view DESIGN TIPS.