05 — Negative Tests (FK / CHECK / UNIQUE rejection)

Live output of N1–N6. Each is isolated in its own SAVEPOINT … <failing insert> … ROLLBACK TO SAVEPOINT, so the expected error never aborts the transaction. ON_ERROR_STOP is toggled off for this block, then back on. Objective 7 (invalid row rejected) — exceeded: 6 distinct rejections proven.

5.1 Results

#	Constraint exercised	Insert attempted	Server error (verbatim DETAIL)	Verdict
N1	partial-UNIQUE uq_gov_obj_accountable	2nd active accountable for approval_requests/policy	duplicate key value violates unique constraint "uq_gov_obj_accountable" · Key (object_type, object_ref, scope)=(collection, approval_requests, policy) already exists.	rejected
N2	FK …_owner_gov_code_fkey	owner GOV-PHANTOM (not in registry)	violates foreign key constraint "governance_object_ownership_owner_gov_code_fkey" · Key (owner_gov_code)=(GOV-PHANTOM) is not present in table "governance_registry".	rejected
N3	FK …_scope_fkey	scope nonexistent_scope	violates foreign key constraint "governance_object_ownership_scope_fkey" · Key (scope)=(nonexistent_scope) is not present in table "governance_responsibility_scope".	rejected
N4	CHECK …_owner_kind_check	owner_kind='owner' (not in enum)	violates check constraint "governance_object_ownership_owner_kind_check"	rejected
N5	CHECK chk_delegated_ttl	owner_kind='delegated', effective_to=NULL	violates check constraint "chk_delegated_ttl"	rejected
N6	FK …_ruleset_version_fkey (candidate fail-closed)	governance_candidate_state with ruleset_version='RULESET-DOES-NOT-EXIST'	violates foreign key constraint "governance_candidate_state_ruleset_version_fkey" · Key (ruleset_version)=(RULESET-DOES-NOT-EXIST) is not present in table "governance_ruleset".	rejected

5.2 What each proves

• N1 — the one-accountable-per-(object,scope) invariant is enforced by the partial-unique index; a second accountable owner cannot be created. This is why the conflict view (doc 04 §4.5) returns 0 on the real store.
• N2/N3 — ownership cannot reference a non-existent governance actor or a non-existent responsibility scope; the owner taxonomy and scope set are closed.
• N4 — owner_kind is restricted to {accountable, supporting, delegated, exception}; arbitrary roles are rejected.
• N5 — a delegated owner must carry an expiry (effective_to); delegation cannot be perpetual — TTL is structurally mandatory.
• N6 — fail-closed candidacy: a candidate verdict cannot exist without a registered ruleset version. Verdicts are always anchored to a known ruleset (the decaying-candidacy design depends on this).

5.3 Transaction survived all six

After each ROLLBACK TO SAVEPOINT the transaction remained alive and the subsequent step ran normally (the INTX_OUT_OF_SCOPE and INTX_TRANSIENT_PERSISTED probes after the negative block both returned, doc 06). No negative-test row persisted (final ROLLBACK + independent census confirm governance_object_ownership=0, governance_candidate_state=0).

5.4 Negative-test verdict

PASS (exceeded). 6 of 6 invalid rows rejected by the exact constraint intended — UNIQUE, two FKs, two CHECKs, and one fail-closed candidate FK. The substrate's integrity rails are live and enforced.