Relationships and Cardinality - Nextedy Documentation

What relationship cardinalities are supported?

Powersheet supports two relationship cardinality types in the data model, plus the implicit reverse of many-to-one:

Cardinality	Direction	Navigation Property	UI Behavior
`many-to-one`	`direct`	Scalar (e.g., `chapter`)	Single-value reference picker
One-to-many	`back` (reverse of N:1)	Collection (e.g., `userNeeds`)	Child rows (new sheet level)
`many-to-many`	`back`	Collection via association (e.g., `systemRequirements`)	Multi-item reference picker

Relationships are defined in the relationships array of the data model and map to Polarion link roles via the linkRole property. Each relationship specifies a direct and back navigation property name.

How do I configure a many-to-one relationship?

A many-to-one relationship links multiple entities to a single target. Use the direct navigation property name in your source expand and column binding:

relationships:
  - from: UserNeed
    to: Chapter
    cardinality: many-to-one
    storage: linkedWorkItems
    linkRole: parent
    direct:
      name: chapter
    back:
      name: userNeeds

In the source, expand using the direct name. In columns, bind with chapter for a reference picker or chapter.title for a read-only display of the referenced entity’s title.

How do many-to-many relationships differ from many-to-one?

Many-to-many relationships use an association entity between the two types. This requires a two-level expand in the source configuration and dot-notation in column bindings:

# Source: two-level expand
sources:
  - id: user_needs
    query:
      from: UserNeed
    expand:
      - name: systemRequirements
        expand:
          - name: systemRequirement

# Columns: dot-notation binding
columns:
  systemRequirements.systemRequirement:
    title: System Requirement
    list:
      search:
        - objectId
        - title
  systemRequirements.systemRequirement.title:
    title: SysReq Title
    hasFocus: true

The first level (systemRequirements) reaches the association entity; the second level (systemRequirement) reaches the actual target entity. See the Data Model Guides for walkthrough examples.