A — Cut / Reconstruct Evidence

Capability: source document → IU pieces → reconstructed original order, with hash/diff/ordering evidence. Verdict: PASS for automatic, deterministic reconstruction. Cut automation gap documented (see §A.5). Channel: read-only (query_pg). Mutation: none.

A.1 Command & function

• public.fn_iu_reconstruct_source(p_doc_code text) RETURNS TABLE(source_position, sort_order, section_type, section_code, canonical_address, depth, gap_before, iu_id) — STABLE.
• Content hash per piece: unit_version.content_hash (sha256 hex of body via fn_content_hash).

A.2 Inputs

Two pre-existing cut corpora chosen as proven datasets:

• DIEU-37 → fn_iu_reconstruct_source('knowledge/dev/laws/dieu37-governance-organization-law.md')
• DIEU-35 → fn_iu_reconstruct_source('DIEU-35')

(Discovered cut corpora, information_unit.doc_code grouped: DIEU-35=36, DIEU-28=27, DIEU-32=23, dieu37=17, dieu39=16, dieu38=8.)

A.3 Ordering integrity (raw output)

doc	pieces	min_pos	max_pos	positions_contiguous	positions_unique	sort_strictly_increasing	gap_before_count
DIEU-35	36	1	36	true	true	true	0
DIEU-37	17	1	17	true	true	true	0

Interpretation: every source position 1..N is present exactly once, sort_order is strictly monotonic, and there are zero gaps — the original document order is fully reconstructable.

A.4 Deterministic reconstruction digest (hash/diff evidence)

md5(string_agg(canonical_address || ':' || content_hash, '|' ORDER BY source_position)):

doc	pieces	pieces_with_hash	reconstruction_digest
DIEU-37	17	17	33e5a1a309833e94e251e829dc5644c5
DIEU-35	36	36	b079d61527d3aef34adeaa4cf4d4dee1

Every piece has a content hash; the digest is recomputable by any reviewer and will change if any piece body or the ordering changes — i.e. it is a tamper-evident reconstruction fingerprint.

Per-piece evidence — DIEU-37 (17 pieces, all version_seq=1)

pos	section_code	canonical_address	v	body_len	content_hash[:16]
1	title	DIEU-37-v3.3#title	1	513	3eccc6ee7d7f0d3c
2	ops-note	DIEU-37-v3.3#ops-note	1	546	6b0fd7860a4d6257
3	goal	DIEU-37-v3.3#goal	1	1234	04d6cb0f01d086d1
4	missions	DIEU-37-v3.3#missions	1	1348	d6d2377e1c053b64
5	terms	DIEU-37-v3.3#terms	1	1140	9a31770b2e39b197
6	core	DIEU-37-v3.3#core	1	746	f0fa69ce22e20bdb
7	scope	DIEU-37-v3.3#scope	1	1271	04187f0457235d4f
8	principles	DIEU-37-v3.3#principles	1	3929	c04a03be90679ac1
9	schema	DIEU-37-v3.3#schema	1	4619	2d9dfa668a93fdcb
10	dot	DIEU-37-v3.3#dot	1	858	fc6c4697e0cc089d
11	matrix	DIEU-37-v3.3#matrix	1	517	21561d3011f75029
12	pg-catalog	DIEU-37-v3.3#pg-catalog	1	190	dc5bb0981c10cc11
13	law-links	DIEU-37-v3.3#law-links	1	188	ea0007a778ca91bf
14	seed	DIEU-37-v3.3#seed	1	193	2ebeaf95d546d9d5
15	debt	DIEU-37-v3.3#debt	1	966	fb519737f2e39f2c
16	triggers	DIEU-37-v3.3#triggers	1	1119	f8fafacd398844a5
17	changelog	DIEU-37-v3.3#changelog	1	1090	8423f5e4ebceff7d

Depth tree: title at depth 0 (document root), all 16 body sections at depth 1.

A.5 Cut automation — what exists and the exact gap

Automatic reconstruction: fully automatic and deterministic (above) — one function call rebuilds the ordered document from its IU pieces.

Automatic cut: exists only through the approved-manifest pipeline — dot_iu_cut_from_manifest → fn_iu_cut_from_manifest (G1–G7 guards, single atomic txn) → loops fn_iu_create to birth each piece. It consumes an already-approved cut manifest (a Điều 32 governance artifact).

Exact gap: there is no standalone "feed a raw document → auto-segment → auto-cut" command. Segmentation of a raw source into the manifest (the decision of where the section boundaries are) is an upstream/curated step; the DB-side cut is the governed materialisation of that manifest. So:

• Raw-text → section manifest: manual/upstream (gap).
• Approved manifest → IU pieces: automatic (fn_iu_cut_from_manifest).
• IU pieces → reconstructed source: automatic + deterministic (fn_iu_reconstruct_source, proven above).

This run used prior cut data (DIEU-37 / DIEU-35) and did not re-cut, per the safe-default instruction.

A.6 What a human can look at

Run SELECT * FROM fn_iu_reconstruct_source('knowledge/dev/laws/dieu37-governance-organization-law.md') ORDER BY source_position; — the 17 rows come back in original document order. Recompute the digest with the query in §A.4 and confirm it equals 33e5a1a3….

A.7 Safety

Read-only. No rows created/updated/deleted. No gate touched.