Schema Validation

Schema validation ensures that ontology definitions are consistent, complete, and aligned with physical data sources. The validation engine checks object type integrity, relationship consistency, mapping correctness, and governance compliance.

Validation Rules

Object Type Validation

Rule	Description	Severity
Unique names	No duplicate object type names within a tenant	Error
Required properties	At least one property must be defined	Error
Valid data types	All property data types must be recognized	Error
Description required	Description must be non-empty	Warning
Governance required	Owner and classification must be set	Warning

Relationship Validation

Rule	Description	Severity
Target exists	Target object type must exist	Error
No circular references	Detect circular relationship chains	Error
Inverse consistency	Inverse relationship must reference back correctly	Warning
Cardinality match	Both sides of the relationship agree on cardinality	Error

Mapping Validation

Rule	Description	Severity
Source exists	Physical table or endpoint must be accessible	Error
Column exists	All mapped source columns must exist	Error
Type compatibility	Source column types must be compatible with property types	Warning
Coverage	All required properties must have mappings	Warning

Validation API

POST /v1/ontology/validate

Request:
{
  "objectTypeId": "ot-abc-123",
  "checks": ["object_type", "relationships", "mappings", "governance"]
}

Response:
{
  "valid": false,
  "errors": [
    {
      "check": "relationships",
      "rule": "target_exists",
      "message": "Target object type 'OrderItem' not found",
      "path": "relationships[0].target_type"
    }
  ],
  "warnings": [
    {
      "check": "mappings",
      "rule": "coverage",
      "message": "Property 'phone_number' has no datasource mapping",
      "path": "properties[3]"
    }
  ]
}

Bulk Validation

Validate all object types in a tenant ontology:

POST /v1/ontology/validate/all

Response:
{
  "totalObjectTypes": 25,
  "valid": 22,
  "invalid": 3,
  "results": [...]
}

Pre-Deployment Validation

Before deploying ontology changes to production, the validation engine runs a comprehensive check:

Phase	Checks
Syntax	Valid JSON/YAML, required fields present
Semantic	Relationship consistency, type compatibility
Physical	Datasource accessibility, column existence
Governance	Owner set, PII fields classified, retention configured

Migration Validation

When updating an existing ontology, the validator checks for breaking changes:

Change Type	Validation
Property removed	Check if any downstream consumers reference it
Type changed	Check backward compatibility
Relationship removed	Check if any queries depend on it
Property renamed	Check all datasource mappings

Object Types -- Object type definitions
Datasource Mapping -- Physical mappings
API Reference -- Full API documentation

Datasource Mapping GraphQL API