Relational Fields

Three field types connect tables and derive data from those connections. They form a chain: a relationship defines the link, then lookup and rollup read or aggregate data through it. (The related count field — categorized as Advanced — also traverses a relationship.)

Type	Purpose
relationship	Creates a foreign-key link to another table. Foundation for the rest.
lookup	Reads a single field value from a related record. Read-only.
rollup	Aggregates a field across many related records (sum, avg, …).

relationship

Creates a foreign-key link to another table.

Property	Description
relatedTable	Required. Name of the target table to link to. Must match an existing table.
relationType	Cardinality. Defaults to many-to-one. Common values: one-to-one, many-to-one, one-to-many, many-to-many.
foreignKey	Custom foreign-key column name (used for one-to-many). Auto-generated when omitted.
displayField	Field from the related table shown in the UI (e.g. name instead of the raw id).
onDelete	Referential action when the related row is deleted (e.g. cascade, set-null, restrict, no-action).
onUpdate	Referential action when the related primary key is updated.
reciprocalField	Field name for the inverse (bidirectional) link on the related table.
allowMultiple	Boolean. Allows linking to multiple records (defaults to true for many-to-many).
limitToView	Restricts selectable related records to those visible in a named view of the related table.

- id: 1
  name: customer
  type: relationship
  relatedTable: Customers
  relationType: many-to-one
  displayField: full_name
  onDelete: set-null
  reciprocalField: orders

lookup

Displays a field value pulled from a related record via an existing relationship. Read-only and auto-updated.

Property	Description
relationshipField	Required. Name of the relationship field to traverse (must exist in the same table).
relatedField	Required. Field on the related table whose value to display.
filters	Optional filter expression narrowing which related records are considered.

- id: 2
  name: customer_email
  type: lookup
  relationshipField: customer
  relatedField: email

rollup

Aggregates values from many related records.

Property	Description
relationshipField	Required. Name of the relationship field connecting to the related table.
relatedField	Required. Field on the related table to aggregate.
aggregation	Required. Aggregation function (e.g. SUM, AVG, MIN, MAX, COUNT).
format	Display format for the aggregated result (e.g. currency, number, percentage).
filters	Optional filter applied before aggregation.

- id: 3
  name: total_sales
  type: rollup
  relationshipField: orders
  relatedField: amount
  aggregation: SUM
  format: currency

See Relationships for a deeper look at cardinalities, referential actions, reciprocal links, and displayField.