How to configure direct relations¶

Belongs to¶

models:
  Post:
    relations:
      Author:
        kind: belongs_to
        model: User
        local_key: user_id
        foreign_key: id
        inverse: Posts
        lazy_query: GetUser
        eager_query: ListUsersByIDs
        nullable: false

Generated operations:

author, err := post.Author().Get(ctx)
post.Author().Associate(user)

Dissociate is generated only when the foreign key is nullable.

Has many¶

models:
  User:
    relations:
      Posts:
        kind: has_many
        model: Post
        local_key: id
        foreign_key: user_id
        inverse: Author
        lazy_query: ListPostsByUser
        eager_query: ListPostsByUserIDs

Generated operations:

posts, err := user.Posts().Get(ctx)
post := user.Posts().New()

New() attaches the new child to the same session and assigns the parent key when available. It does not persist the child.

Has one¶

Configure similarly to has_many, but require a :one lazy query and define the expected behavior when no row exists.

Many to many¶

relations:
  Tags:
    kind: many_to_many
    model: Tag
    local_key: id
    target_key: id
    lazy_query: ListTagsByPost
    attach_query: AttachTagToPost
    detach_query: DetachTagFromPost
    sync_queries:
      list: ListTagIDsByPost
      attach: AttachTagToPost
      detach: DetachTagFromPost

Terminal mutation operations require explicit sqlc queries:

err := post.Tags().Attach(ctx, tagA, tagB)
err := post.Tags().Detach(ctx, tagA)
err := post.Tags().Sync(ctx, tagA, tagC)

The generator does not invent pivot-table SQL.

Many-to-many eager loading is not generated in this release.

Enforce session identity¶

Associate, Attach, and Sync reject models attached to a different session. The initial release also rejects unsaved related models without usable identifiers.