Audit timestamps & UUID keys — Examples

Audit timestamps & UUID keys

A Base abstract type gives every table a UUID primary key, a created_at set once on insert, and an updated_at that touches itself on every update. Types that extend Base inherit all three.

abstract type Base {
  required id: uuid {
    default := gen_uuid();
    constraint exclusive;
    constraint pk;
  };
  required created_at: datetime { default := datetime_current(); };
  required updated_at: datetime {
    default := datetime_current();
    rewrite update := datetime_current();
  };
}

type Article extends Base {
  required title: str;
}

• gen_uuid() / datetime_current() are Axel builtins that lower to gen_random_uuid() (via pgcrypto) and now().
• The rewrite update := datetime_current() on updated_at becomes a BEFORE UPDATE trigger, so the column is stamped in the database — you never set it from application code. See Rewrites.

Article inherits the columns and the trigger; a plain insert only needs title:

insert Article { title := $title<str> };

From generated code

Save that query as create_article.aql and axel codegen produces a typed createArticle function (and a runner.query.createArticle method). The returned row carries the DB-populated id, createdAt, and updatedAt:

TypeScript

const article = await runner.query.createArticle({ title: "Hello" });
// article.id, article.createdAt, article.updatedAt are set by the database

Go

article, err := runner.Query.CreateArticle(ctx, gen.CreateArticleParams{Title: "Hello"})
// article.ID, article.CreatedAt, article.UpdatedAt are set by the database

Because Base is abstract, it produces no table of its own — it’s a mixin you add to any concrete type (Inheritance).