[CAY-2739] Mapping Proposal: replace "toDepPk" with "fk"

• Type: Improvement
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Fix Version/s: 5.0-M2
• Assignee: Nikita Timofeev
• Reporter: Andrus Adamchik
• Created: 03/Jul/22 10:27
• Updated: 01/Nov/24 13:52

Description

"toDepPk" is a DbRelationship property that hints that Cayenne should take the value of the join on the source side and propagate it to the target side. It only applies to PK-to-PK relationships.

It is an artificial construct with nothing equivalent on the DB side, so it may be confusing as to what it means. Moreover it is limited to PK-PK relationships, meaning that we can't propagate values if the source is not a PK.

I suggest that we replace "toDepPk" with a complementary "fk" property that is both well-understood and equally applies to every relationship. "toDepPk" will be a special case of "fk=false" relationship. In most cases it can be auto-calculated (if one side is a PK, and another one is not), so hopefully it will not create extra mapping work.