fix(GIT-1370): ADR cleanup pass for coverage-report Bucket 4

[WilcoLouwerse]

Summary

Closes #1370. Addresses the Bucket 4 findings from openspec/coverage-report.md generated 2026-04-30 (parent: ConductionNL/.github#27).

• SchemaMapper.php:892 — replaced print_r($value, true) with json_encode($value) for the error-message string conversion (ADR-003 / forbidden-debug-calls).
• Audit of all 10 raw db->prepare() sites — each now carries an inline comment explaining why QueryBuilder cannot express the query and noting MariaDB compatibility status.

The audit also surfaced two real MariaDB-incompat bugs that were fixed in the same pass since the codebase already contained portable counterparts to mirror:

1. ReferentialIntegrityService.php:372 used current_schema() unconditionally — that function is PostgreSQL-only and would fail on MariaDB. Now branches on the database platform (DATABASE() for MySQL/MariaDB, current_schema() for PostgreSQL), mirroring the established pattern in MagicMapper.php:1697-1707.
2. RegisterService.php:418 used CAST(... AS VARCHAR) unconditionally — VARCHAR (without length) is non-standard on MariaDB. Now branches on platform (CAST AS CHAR for MariaDB/MySQL, CAST AS VARCHAR for PostgreSQL), mirroring MagicMapper.php:1346-1349.

Audit findings (per site)

File	Line	Why raw SQL	MariaDB status
RegisterService.php	442	UNION ALL across N dynamically-named magic tables	✅ after CAST fix
ReferentialIntegrityService.php	373	information_schema.tables metadata query	✅ after current_schema() fix
ReferentialIntegrityService.php	902	Platform-conditional JSON_CONTAINS / jsonb @> operators	✅ already platform-aware
LinkedEntityEnricher.php	121	Foreign Mail-app table (oc_mail_messages)	✅
LinkedEntityEnricher.php	161	Foreign DAV/Contacts table (oc_cards)	✅
LinkedEntityEnricher.php	247	Foreign DAV/Calendar table (oc_calendarobjects)	✅
LinkedEntityEnricher.php	301	Foreign DAV/Calendar table (oc_calendarobjects)	✅
LinkedEntityEnricher.php	347	Foreign Talk-app table (oc_talk_rooms)	✅
LinkedEntityEnricher.php	400	Foreign Deck-app tables (joined cards/stacks/boards)	✅
CacheHandler.php	1770	Runtime-resolved magic table + name column from fixed allowlist	✅

The issue body summary said "8" but the table actually lists 10 occurrences — all 10 are covered.

Test plan

• php -l clean on all five edited files (verified locally)
• phpcs produces no new warnings beyond pre-existing long-line warnings (verified locally)
• CI pipeline passes
• Manual verification on MariaDB target: RegisterService::getSchemaObjectCounts() and ReferentialIntegrityService::buildSchemaRegisterMap() no longer raise SQL syntax errors

🤖 Generated with Claude Code

[github-actions]

Quality Report — ConductionNL/openregister @ cf1f4f5

Check	PHP	Vue	Security	License	Tests
lint	✅
phpcs	✅
phpmd	✅
psalm	✅
phpstan	✅
phpmetrics	✅
eslint		✅
stylelint		✅
composer			✅	✅ 147/147
npm			✅	✅ 598/598
PHPUnit					❌
Newman					❌
Playwright					⏭️

---

Quality workflow — 2026-05-05 22:11 UTC

Download the full PDF report from the workflow artifacts.

[MWest2020]

Review — getest op MariaDB 11.2

Lokaal getest tegen MariaDB 11.2 + Nextcloud 33.0.3 (vendor via composer install --no-dev):

Setup

• app:enable openregister → schoon, geen SQL fouten in migraties
• Register testreg + Schema testschema aangemaakt; magic table oc_openregister_table_1_1 correct gegenereerd

Pad 1 — RegisterService::getSchemaObjectCounts() (CAST AS CHAR fix)

• GET /api/registers?_extend[]=schemas&_extend[]=@self.stats na het aanmaken van een object
• Response: {"objects":{"total":1,"deleted":0,"invalid":0,"locked":0,"size":0}}
• → de UNION ALL met CAST({schemaId} AS CHAR) heeft daadwerkelijk gedraaid op MariaDB. Vóór de fix faalde dit op CAST AS VARCHAR zonder lengte. ✅

Pad 2 — ReferentialIntegrityService::buildSchemaRegisterMap() (DATABASE() fix)

• DELETE /api/objects/testreg/testschema/{uuid} → soft-delete OK, _deleted ingevuld in magic table
• Path: DeleteObject::canDelete() → ensureRelationIndex() → buildSchemaRegisterMap() (information_schema.tables met DATABASE())
• Geen SQL errors in nextcloud.log voor dit pad. ✅

Logscan

• 0 hits op sql syntax|sqlstate|near "varchar"|near "current_schema"|RegisterService] Error|buildSchemaRegisterMap.*error over de hele sessie

Twee kleine nits (geen blocker)

Nit 1 — consistentie met precedent
RegisterService.php:398 kiest CAST AS VARCHAR voor de Postgres-tak, maar het precedent in lib/Db/MagicMapper.php:1346-1349 gebruikt {$col}::text voor Postgres. Beide werken; mirror-voor-mirror zou ::text literal-consistenter zijn. Geen functioneel verschil.

Nit 2 — pad in PR-body
De PR-beschrijving verwijst naar MagicMapper.php:1697-1707 en :1346-1349 zonder pad. Het bestand is recent verplaatst van lib/Service/MagicMapper.php → lib/Db/MagicMapper.php. Voor toekomstige lezers handig om het volle pad te noemen.

LGTM verder, fix is correct, klein en gefocust. ✅