data.reference_cycle

Two or more entities refer to each other through required fields, so none of their records could ever be created first.

Area 5, Entities, stores and migrations; not declinable; the next step is usually the human's.

Why Jadpo refuses it

A required reference must point at a record that already exists. Here a Team needs its lead, a Member, and a Member needs its Team. The first team can't be created without a member, and the first member can't be created without a team, whatever on_delete: says.

Jadpo won't choose which reference becomes optional, because that decides which record can exist on its own for a while.

What it looks like

main.jadpo:

entity Team {    id: Uuid    lead_id: Member.id {        on_delete: OnDelete.restricted    }}entity Member {    id: Uuid    team_id: Team.id {        on_delete: OnDelete.restricted    }}

   | 3 |     lead_id: Member.id {   |     ------- and this one10 |     team_id: Team.id {   |     ^^^^^^^ required reference

(human) at the end of the next: line tells your coding agent to stop and ask you which fix you want, because the choice is yours to make: it decides whether a team can be without a lead, or a member without a team.

How to fix it

The question is which record may exist without the other.

If a team may be without a lead, make lead_id optional. An optional reference can also be cleared when its member is deleted:

    lead_id: Member.id? {        on_delete: OnDelete.cleared    }

A team is created with no lead, then its members, and then its lead is set. Deleting the lead leaves the team without one.

If a member may be without a team, make team_id optional instead:

    team_id: Team.id? {        on_delete: OnDelete.cleared    }

A member is created with no team, then the team with that member as its lead, and then the member joins it. Deleting a team leaves its members without one.

Related

• References and on_delete