Prisma implicit many-to-many relations create a hidden join table you cannot query

Declaring a many-to-many by putting a list field on both models makes Prisma manage the join table itself. It is named by joining the two model names alphabetically after a leading underscore, with columns A and B holding the foreign keys, no primary key of its own, and a unique index on the pair.

Because the table is not in the Prisma schema it cannot be selected from, filtered on, or given extra columns such as a created_at or a role. Adding one later requires converting to an explicit relation, which means a data-moving migration on a live table. Choose an explicit join model up front whenever the relationship might ever carry attributes. When a schema is introspected from an existing database, Prisma recognises a table as an implicit relation only when it matches that exact naming and shape.