07 — First Durable Structure Operation — Apply / Verify Result

Referenced by sql/iu-core/runtime/140_structure_op_first_durable.sql.

Operation

Field	Value
operation_id	b37fb5f1-a89e-4780-a9c3-1a8f35410a1d
operation_type	reparent_piece
actor_ref	iu_core_runtime_140
child IU	D38-DIEU35-S4-P1-1 (5410e681-6d53-48ba-b202-076ecc857115)
new parent	D38-DIEU35-S4-P1 (3477ff71-b8a4-4dd8-b854-d86c1567ba83)
prior parent	null (was flat / root)

Why this candidate (live discovery)

The survey found all 158 IUs flat. canonical_address encodes the intended tree. D38-DIEU35-S4-P1-1 is a leaf (0 children, lifecycle_status='draft'), and its address minus the last -segment is D38-DIEU35-S4-P1, an existing root. Nesting it is semantically correct and the lowest-risk durable operation: one row of information_unit, one iu_tree_path row, no subtree. runtime/140 re-derives the parent and aborts (transaction rollback) unless the child is found, flat, a leaf, and in the same document.

Envelope (one committed transaction; gate opened + closed within it)

Phase	Result
plan	operation b37fb5f1-..., status planned
apply	ok=true, status enacted, tree_paths_refreshed=1, relation 7961cbb4-ebfb-4f2f-abfc-a658ddf1bb38 written
verify	ok=true — tree_path_ok, relation_ok, tree_acyclic all true; live_parent = expected_parent
gate	re-closed (iu_core.structure_ops_enabled='false') — layer ends inert

Independent read-back (post-commit)

Check	Value
v_iu_structure_operation_log	1 row — reparent_piece / enacted / relation_count=1
iu_relation	1 — contains / active, created_by iu_core_runtime_140
child information_unit	parent_or_container_ref = 3477ff71-..., lifecycle draft
child iu_tree_path	depth 1, parent 3477ff71-..., root 3477ff71-..., path length 2
tree consistency	iu_tree_path 158 = v_iu_tree 158 = live IUs 158

Reversal (not executed — operation left correctly applied)

The operation is a genuine, correct improvement to the data model and is left enacted. To reverse it: open the gate, SELECT fn_iu_structure_op_rollback('b37fb5f1-a89e-4780-a9c3-1a8f35410a1d'), close the gate. The full compensation snapshot is in iu_structure_operation.impact_summary (prior_parent=null, relation_written=7961cbb4-..., relation_retired=null). The rollback path was independently proven by sandbox/050 on real rows.