SHACL-AF Non-Blocking Data-Quality Rules

Context

A pattern has emerged across four kind: pattern ODRs ratified through 2026-05-27: each authored a SHACL-AF rule (sh:rule / sh:sparql) that materialises a non-blocking data-quality assertion — succession, deprecation, lineage — into the validation report at sh:Info or sh:Warning severity, NOT as sh:Violation. The data being asserted is correct under its temporal or contextual scope (UPRN succession is administrative; deprecation is a lifecycle state; INSPIRE succession is rare-but-real); the rule is informative, not normative-breaking.

The four citing sites:

1. ODR-0005 §6a — UPRN succession chain (Cagle Q4 amendment, S005). Materialises opda:previousUPRN → opda:uprn chain at sh:Info; rebuts Hellmann et al. (DBpedia 2017) LLM-fallback-to-owl:sameAs failure mode for identifier succession.
2. ODR-0009 (Claims, Evidence & Provenance — when S009 runs). Anticipated: PROV-O Activity reification + prov:wasDerivedFrom chain materialisation for evidence-collection events.
3. ODR-0015 §4a — INSPIRE Identifier / OS AddressBase succession (S015 Q4); re-instantiates the §6a pattern for the Address Kind’s contingent identifier (per S005’s Quality-on-Substance-Kind precedent).
4. ODR-0011 §5a — Concept deprecation-chain (Cagle Q5 amendment, S011). Materialises owl:deprecated true + dct:isReplacedBy chain at sh:Info (with-succession) or sh:Warning (without-succession).

Per ODR-0001 A9 §Artefact identity test — the fourth-citing-site threshold for pattern-extraction is satisfied. S011 §Consequences flagged the spawn-rule as fired. This ODR extracts the pattern as a reusable artefact-engineering decision; the four citing sites become implements: of it; future SHACL-AF rule authoring re-instantiates the pattern rather than re-deciding the discipline per ODR.

The pattern is kind: pattern per ODR-0001 A9 §What an ODR records (a)/(b)/(c) discipline: UFO/DOLCE meta-category (Method/plan code per ODR-0011 §8a — the rule is a procedural plan for materialising data-quality assertions), IC over named hard cases (rule severity; rule placement in graph; rule consumption by tooling), artefact realisation (sh:rule / sh:sparql SHACL-AF Turtle template).

Decision

The diagram below illustrates how a SHACL-AF non-blocking rule routes a data-quality assertion to sh:Info/sh:Warning rather than sh:Violation, contrasting it with ordinary normative-blocking SHACL constraints.

Adopt the SHACL-AF non-blocking data-quality rules pattern as the canonical mechanism for materialising data-quality assertions that are informative, not normative-breaking: a sh:rule (or sh:sparql form) on the targeted class, returning the assertion’s value via SELECT $this ?fact …, with sh:severity sh:Info (state-with-substantive-succession) or sh:Warning (state-without-succession), placed in the shapes graph (opda-shapes.ttl per ODR-0004 §3a). The rule’s output is machine-consumable data — read by SHACL validators, LLM tooling (per Hellmann et al. DBpedia 2017 LLM-fallback rebuttal), odr-review lint extensions, audit-trail consumers. The rule is never sh:Violation severity (Violation is reserved for normative-breaking; the assertions this pattern materialises are correct under their temporal/contextual scope).

Rules

These rules constrain every implements: of this pattern.

1. sh:rule or sh:sparql form. The rule is authored as either a sh:Rule (SHACL Advanced Features Recommendation §2) or a sh:sparql constraint with sh:select body (SHACL Core §5.2.6 SPARQL-based constraints). Both forms admissible; choice depends on whether the materialised triples need to enter the data graph (use sh:Rule) or only the validation report (use sh:sparql).
2. Severity at sh:Info or sh:Warning, NEVER sh:Violation. The data is correct; the rule is informative. sh:Info for assertions with substantive succession recorded (prov:wasDerivedFrom / dct:isReplacedBy chains present). sh:Warning for assertions without substantive succession (deprecation-without-replacement; retirement-without-successor).
3. Placement in shapes graph (opda-shapes.ttl). Per ODR-0004 §3a three-graph separation, the rule lives in the shapes graph, NOT the annotation graph (opda-annotations.ttl). The CI test ASK { GRAPH opda:annotations { ?s a sh:NodeShape } } returns false; this rule’s sh:NodeShape declaration is in opda:shapes.
4. SELECT $this ?fact ?succession SPARQL skeleton. The rule’s SPARQL body returns at minimum the target node ($this) and the materialised assertion. The sh:message template references the captured variables for human-readable reporting AND machine-readable downstream parsing.
5. sh:message is machine-parseable. The message template uses {?var} placeholders that the SHACL validator interpolates; downstream tooling (LLM consumers, lint extensions) parses the rendered message to extract the structured assertion. AVOID natural-language paragraphs in sh:message; PREFER structured key-value or template-literal form.
6. No owl:sameAs materialisation. A non-blocking data-quality rule MUST NOT produce owl:sameAs triples (inherits ODR-0005 Rule 5 anti-pattern — owl:sameAs propagates irreversibly under reasoning). Materialise via prov:wasDerivedFrom, dct:isReplacedBy, skos:exactMatch, or opda:identifiesSameProperty per the consuming ODR’s discipline.
7. Consuming ODR cites this pattern via implements:. Each consuming ODR declares implements: [..., ODR-0017] in its frontmatter (alongside its other implements: of ODR-0003). The ## References section cites this ODR’s pattern URL for the authoring discipline.

Operational specifications

1a. Canonical template (SHACL-AF rule form)

opda:<DomainQuality>NonBlockingRule a sh:NodeShape ;
    sh:targetClass <opda:TargetKind> ;
    sh:sparql [
        sh:select """
            SELECT $this ?currentFact ?priorFact WHERE {
                $this <opda:currentPredicate> ?currentFact .
                OPTIONAL { $this <opda:priorPredicate> ?priorFact }
            }
        """ ;
        sh:severity sh:Info ;     # sh:Warning if no substantive succession
        sh:message "{$this} <opda:domain-quality-relationship> {?currentFact} ← {?priorFact} (where defined)"
    ] .

Per ODR-0004 §3a three-graph separation: the rule sits in opda-shapes.ttl; the data graph (e.g. opda-instances.ttl or per-Property graphs) carries the data the rule reads; the validation report is the rule’s output channel.

2a. Three-tier severity decision rule

The following flowchart traces the evaluation path of a single SHACL-AF rule instance from the shapes graph through the validator to its downstream consumers.

3a. Machine-consumability requirement

Per Hellmann et al. (DBpedia 2017) LLM-fallback rebuttal (Cagle S005 §6a + S011 §5a citations): the rule’s output MUST be machine-parseable by:

1. SHACL validators (the canonical consumer — produces sh:ValidationReport triples; consumer queries sh:resultMessage and sh:focusNode).
2. odr-review lint extensions — reads the rule’s source from opda-shapes.ttl; verifies severity is in {sh:Info, sh:Warning} (rejects sh:Violation); verifies placement in shapes graph; verifies sh:message template uses placeholder form.
3. LLM tooling — queries the validation report for sh:resultMessage literals; parses the structured template form for the non-blocking-quality assertion content; substitutes the assertion for rdfs:comment-based natural-language fallback (which Hellmann et al. documented as failing on rename/paraphrase/translation).
4. Audit-trail consumers — read the sh:Info/sh:Warning entries as data-quality lineage records; correlate with the data graph’s reified event resources.

4a. UFO/DOLCE meta-category — Method/plan code (A9 (a) discharge)

Per ODR-0011 §8a’s seven-category UFO framework, this pattern is a Method/plan code — the SHACL-AF rule is a procedural plan for materialising a data-quality assertion into the validation report. The plan is reusable across domains (UPRN succession; deprecation; INSPIRE re-issue; future Person-ID succession). The plan’s executor is the SHACL-AF-aware validator (the canonical consumer); other consumers (lint, LLM, audit) read the executed plan’s output.

dct:source on the UFO category: Guizzardi & Wagner 2010 (action-modelling / method-codes in UFO-A) + Guizzardi 2005 Ch. 4 + ODR-0011 §8a (Council-authored SKOS-binding) + ODR-0017 (this pattern’s plan-code specialisation).

5a. IC over named hard cases (A9 (b) discharge)

A SHACL-AF non-blocking-data-quality rule r₁ at time t₁ and a candidate-individual rule r₂ at time t₂ > t₁ are the same individual iff (i) their sh:targetClass is the same; (ii) their sh:select SPARQL body is structurally equivalent (same WHERE-clause patterns modulo variable renaming); (iii) their severity is the same. Under the following hard cases:

1. Rule extension. A rule’s SPARQL body gains a new OPTIONAL clause without changing the existing patterns → same individual (extension preserves identity).
2. Severity adjustment. A rule’s severity changes between sh:Info ↔ sh:Warning → same individual (severity tier is a refinement, not an identity change). Severity changing to sh:Violation → rule ceases to exist under this pattern; a new (non-pattern) SHACL constraint replaces it.
3. Target-class change. Rule’s sh:targetClass changes → new individual; prov:wasDerivedFrom chains the new rule to the predecessor.
4. Message-template refinement. The sh:message template is rephrased without changing variable references → same individual.
5. Graph relocation. Rule moves from one shapes graph to another (e.g. extracted from one ODR’s profile shapes into a shared shapes module) → same individual; the move is dct:isReplacedBy (in the OLD location’s deprecation) + prov:wasGeneratedBy (in the new location’s instantiation).

6a. Artefact realisation (A9 (c) discharge)

The artefact realisation is the Turtle SHACL-AF rule above (§1a), placed in opda-shapes.ttl per ODR-0004 §3a. The rule is emitted by the generator (per ODR-0004 §6a deterministic-emission discipline) reading from a rule-source declaration; the rule’s structure follows the §1a template; the generator MAY parameterise the rule via inputs (target-class, predicates, severity) so each implements: site supplies only the parameters, not the full Turtle.

Alternatives

The diagram below maps each considered alternative to the decision driver that disqualified it, with the chosen pattern shown as the accepted outcome.

• Materialise data-quality assertions in the annotation graph (opda-annotations.ttl). Rejected per ODR-0004 §3a CI test 1 (ASK { GRAPH opda:annotations { ?s ?p ?o . FILTER(STRSTARTS(STR(?p), "shacl-prefix")) } } must return false). SHACL rules in the annotation graph break the three-graph separation; LLM consumers querying the annotation graph would receive shape-graph content as if it were advisory annotations, corrupting both layers.
• Use OWL reasoning + owl:propertyChainAxiom to materialise the succession chain. Rejected per ODR-0005 Rule 5 anti-pattern (no owl:sameAs-equivalent propagation across contexts). OWL property chains produce inferred triples that propagate irreversibly under reasoning; the use case is informative materialisation, not normative-equivalence assertion.
• Encode the data-quality assertion in rdfs:comment only. Rejected per Hellmann et al. (DBpedia 2017) LLM-fallback failure mode — natural-language rdfs:comment is consumed by LLM heuristics, which fail on rename/paraphrase/translation. The structured SHACL-AF rule is the mechanically-readable substitute.
• Bake the rule into each consuming ODR without pattern-extraction. Rejected by ODR-0001 A9 §Artefact identity test fourth-citing-site threshold — the pattern has crossed the threshold for shared abstraction; baking it into each ODR creates four parallel-but-divergent rule authorings, and a future maintainer cannot extract the common discipline.

Consequences

• Four-site implements: retrofitting. ODR-0005 §6a, ODR-0009 (when S009 ratifies its PROV-O rule), ODR-0015 §4a, ODR-0011 §5a all add ODR-0017 to their implements: frontmatter and cite this pattern in their ## References. The retrofit is a follow-up author-only edit; flagged as housekeeping for the next /loop fire or Queen-convened session.
• A9 pressure-test continues to operate. This is the first kind: pattern ODR that is itself a pattern-extraction record (not a domain-modelling pattern). The (a)/(b)/(c) discipline applies; this ODR discharges all three (Method/plan code UFO category; five named hard cases for rule identity; Turtle template artefact).
• odr-review lint extension. Beyond the existing planned extensions (per ODR-0004 §Consequences), the lint should verify: any SHACL-AF rule declaring sh:Info or sh:Warning severity is implements: ODR-0017; conversely, any ODR implements: ODR-0017 MUST place its SHACL-AF rule in opda-shapes.ttl (not annotation graph) AND MUST use the §1a template structure.
• Future succession patterns. ODR-0006 (Agents & Roles, Phase 3a) may produce a fifth citing site (e.g. NI-number renumbering; passport-renewal succession for Person identity). When it does, ODR-0017 is the canonical pattern to implements:; the new rule re-instantiates the template rather than re-deciding the discipline.
• Namespace ratified; record accepted. The inherited ODR-0004 namespace block is lifted (the opda: string was ratified 2026-05-27 — greenfield; no WG), so ODR-0017 is accepted. Generator output for the rule’s opda: declarations may still carry dct:status "draft" as a publication-grade marker, independent of record ratification.

References

• Methodology: ODR-0001 §What an ODR records (per-kind discipline) — A9 amendment 2026-05-27; §Artefact identity test (the fourth-citing-site threshold this ODR satisfies); ODR-0011 §8a (Method/plan code UFO category source).
• Foundation: ODR-0004 §3a (three-graph separation — shape lives in opda-shapes.ttl); §6a (generator-first deterministic-emission discipline).
• W3C / spec: SHACL Core Recommendation §5.2.6 (SPARQL-based constraints); SHACL Advanced Features (sh:rule, sh:Rule) — W3C Working Group Note; SHACL Core §6.5 (severity); PROV-O Recommendation (Moreau & Missier 2013); RDF 1.1 Semantics (Hayes & Patel-Schneider 2014) §6 (owl:sameAs).
• Foundational ontology: Guizzardi 2005 Ontological Foundations Ch. 4 (UFO Method/plan codes); Guizzardi & Wagner 2010 (action-modelling).
• AI-RDF citation: Hellmann et al. 2017 DBpedia 2017 release notes — LLM fallback to owl:sameAs / heuristic class-name matching when assertions are in rdfs:comment only.
• Citing sites (implements: retrofit pending):
  • ODR-0005 §6a — UPRN succession-chain rule (Cagle S005 Q4 amendment).
  • ODR-0009 — PROV-O Claims/Evidence rule (anticipated when S009 ratifies).
  • ODR-0015 §4a — INSPIRE / OS AddressBase succession (S015 Q4).
  • ODR-0011 §5a — Concept deprecation-chain rule (Cagle S011 Q5 amendment).
• Council deliberation provenance: spawned by session-011 §Synthesis + §Consequences (fourth-citing-site spawn-rule fires); authored as Author-only follow-up to S011’s closure per ODR-0001 §Self-amendment process + §Artefact identity test.
• Related ODRs: programme anchor ODR-0003; methodology ODR-0001 §What an ODR records (per-kind discipline for kind: pattern).

The graph below shows ODR-0017’s dependency and implementing relationships as declared in the frontmatter.