# Entities

Find the owner, size and reference page of every table in Products & Services.

The base has 14 tables: six native catalog tables and eight mirrors from Core. The mirrors provide shared identity and organizational context; their records are maintained in Core.

| Table | Documentation | Ownership |
| --- | --- | --- |
| Product Category | [Open reference](/systems/products/entity-product-category) | Products & Services |
| Brand | [Open reference](/systems/products/entity-brand) | Products & Services |
| Price List | [Open reference](/systems/products/entity-price-list) | Products & Services |
| Product | [Open reference](/systems/products/entity-product) | Products & Services |
| Offer | [Open reference](/systems/products/entity-offer) | Products & Services |
| Organization (mirror) | [Open reference](/systems/products/entity-organization) | Core |
| Product Component | [Open reference](/systems/products/entity-product-component) | Products & Services |
| Tags (mirror) | [Open reference](/systems/products/entity-tags) | Core |
| Membership (mirror) | [Open reference](/systems/products/entity-membership) | Core |
| Department (mirror) | [Open reference](/systems/products/entity-department) | Core |
| Person (mirror) | [Open reference](/systems/products/entity-person) | Core |
| Position (mirror) | [Open reference](/systems/products/entity-position) | Core |
| Team (mirror) | [Open reference](/systems/products/entity-team) | Core |
| Classification term (mirror) | [Open reference](/systems/products/entity-classification-term) | Core |

## Cardinality and identifiers

| Relationship | Business rule | What the field allows |
| --- | --- | --- |
| Offer → Product | Exactly one product per offer | Many links; Offer Check flags only a blank |
| Offer → Seller (Organization) | Exactly one seller per offer | Many links; Offer Check flags only a blank |
| Offer → Price List | At most one list per offer | Many links |
| Product Component → Product (whole) and Includes (part) | One whole and one part per line, never the same product | Many links; Component Check flags blanks and an identical pair |
| Product → Brand, Category | At most one each | Many links |
| Product → Alternative To | A substitute points at its main product | Many links; Alternatives is the inverse |

All link fields are multiple-record links. A single-link rule above is a business rule stated in the field description and, where noted, a formula check; it is not a database constraint.

Product # and Offer # are local auto-numbers. The base has no portable identifier such as Core's coreId; readers link through the Airtable sync, not by a stored UUID.