> ## Documentation Index
> Fetch the complete documentation index at: https://learn.nextedy.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Data Model FAQ

> Common questions about configuring the Nextedy POWERSHEET data model — entity types, relationships, cardinality, and expansion paths in Siemens Polarion ALM.

export const LastReviewed = ({date}) => {
  if (!date) return null;
  const formatted = new Date(`${date}T00:00:00Z`).toLocaleDateString("en-US", {
    year: "numeric",
    month: "long",
    day: "numeric",
    timeZone: "UTC"
  });
  return <p className="mt-10 text-sm text-gray-400 dark:text-zinc-500 not-prose">
      Last reviewed on {formatted}
    </p>;
};

<Note title="Terminology">
  In Powersheet, the YAML file defining entity types and relationships is called the **data model** (formerly "domain model"). "Entity type" refers to data model concepts; "work item type" refers to the underlying Polarion type.
</Note>

<Columns cols={2}>
  <Card title="Data Model Basics" icon="circle-question" href="/powersheet/faq/data-model/data-model-basics">
    What is a data model and why do I need one?
  </Card>

  <Card title="Entity Types and Properties" icon="circle-question" href="/powersheet/faq/data-model/entity-types-and-properties">
    How do I define entity types in the data model?
  </Card>

  <Card title="Relationships and Cardinality" icon="circle-question" href="/powersheet/faq/data-model/relationships-and-cardinality">
    What relationship cardinalities are supported?
  </Card>

  <Card title="Configuration Tips" icon="circle-question" href="/powersheet/faq/data-model/configuration-tips">
    Should I start with a complex or simple data model?
  </Card>
</Columns>

<LastReviewed date="2026-07-08" />