[ROOT] / doc / toc / ARCCore / Enum / ARConcepts / ManyToManyRelations

ARCQuery supports many-to-many relations in a simple manner without introducing a third entity type (a third table).

This is done through having foreign keys with cardinality IsMultiple like WholeCollection and IndividualItems.

Example 1), tagging PersonP.CarId with IndividualItems:
Person/42/CarId/1968
Person/42/CarId/1981
Person/43/CarId/1968

Example 2), tagging PersonP.CarId with WholeCollection:
Person/42/CarId = 1968;1981
Person/43/CarId/1968

In both examples person 42 owns two cars (1968 and 1981), but shares car 1968 with person 43.
(you can of course also store many-to-many relations in the traditional RDBMS manner by using a third 'entity' type called PersonCarOwnership or similar).

Generated 2025-05-23 08:07:27.800 UTC