Data Model Reference - Nextedy Documentation

How the Data Model Works

The data model is a YAML configuration file that declares three things:

Entity types — what kinds of objects exist (e.g., UserNeed, SystemRequirement, Hazard)
Relationships — how entity types connect to each other, with cardinality and link roles
Properties — which fields each entity type exposes, mapped to Polarion work item fields

These three layers drive everything downstream: sheet sources determine which entities to query, expansion paths follow relationship definitions, and column bindings resolve against properties.

┌─────────────────────────────────────────────────────────┐
│                     Data Model                        │
│                                                         │
│  ┌──────────────┐     relationships     ┌─────────────┐ │
│  │ EntityType A  ├─────────────────────►│ EntityType B │ │
│  │ - properties  │     cardinality      │ - properties │ │
│  │ - constraints │     linkRole         │ - constraints│ │
│  │ - polarionType│     direct / back    │ - polarionType│
│  └──────────────┘                       └─────────────┘ │
│                                                         │
│         ▼ maps to ▼                 ▼ maps to ▼         │
│    Polarion Work Item Types + Link Roles + Fields       │
└─────────────────────────────────────────────────────────┘

Entity Type Configuration

Data Model Types — Entity type definitions: name, polarionType, nested properties, and plural name generation
Polarion Type Mapping — How polarionType maps domain entities to Polarion work item types, including multi-type mappings

Cardinality — Relationship multiplicity options (one-to-one, one-to-many, many-to-one, many-to-many) and how each affects source expansion and column binding
Link Roles — Mapping data model relationships to Polarion link role identifiers
Navigation Directions — Forward (direct) and reverse (back) navigation properties, naming conventions, and how directions drive expansion paths

Constraints and Access Control

Constraints — Load, create, and pick constraint rules that scope which Polarion items an entity type includes, using Lucene query syntax
Permissions — Entity-level and property-level access control: readable, updatable, createable, and isReadOnly flags
Context Expressions Reference — Dynamic context expressions for runtime evaluation in constraints and filters

Quick Orientation

Concept	Key YAML Property	Reference
Define an entity type	`domainModelTypes.TypeName`	Data Model Types
Map to Polarion	`polarionType`	Polarion Type Mapping
Add fields	`properties`	Properties
Connect entity types	`relationships[]`	Relationships
Set multiplicity	`cardinality`	Cardinality
Name navigation paths	`direct.name` / `back.name`	Navigation Directions
Assign Polarion link	`linkRole`	Link Roles
Restrict loaded items	`constraints`	Constraints
Control editability	`isReadOnly`, `updatable`	Permissions

Start with the Creating Your First Data Model tutorial for a guided walkthrough, then return here for property-level details. For complete working models, see the Example Models Reference.

Relationship between model, sources, and columns

The data model defines what exists. Sheet sources define what to query and expand. Columns define what to display. Navigation property names from the data model are the thread connecting all three layers. See Cardinality for end-to-end examples showing how each cardinality type flows from model through source expansion to column binding.

​How the Data Model Works

​Entity Type Configuration

​Relationships and Navigation

​Constraints and Access Control

​Quick Orientation

How the Data Model Works

Entity Type Configuration

Relationships and Navigation

Constraints and Access Control

Quick Orientation