Schema map & relationships — Choose links or Relation fields

Every link is a one-way arrow: it runs from a starting record to a linked record and carries a name. A record can sit on either end of any number of links, so one-to-many and many-to-many shapes both work. Relation fields are the durable version: defined once on a table, filled in per record, and RowFold keeps the map's arrows in sync with their values. Lookup and Rollup fields — which pull or aggregate values across a relation — are added in a table's field editor, not on the schema map; the map just lists them on the table's card like any other field.