The row object

At the heart of every table module is the row object:

row

export const row = z.object({
  id: z.number().brand<"public.penguins.id">(),
  name: z.string(),
  species: z.string(),
  waddle_speed_kph: z.number(),
  favourite_snack: z.string().nullable(),
  date_of_birth: z.date(),
});

penguins.sql

CREATE TABLE penguins (
  id SERIAL PRIMARY KEY,
  name TEXT NOT NULL,
  species TEXT NOT NULL,
  waddle_speed_kph NUMERIC NOT NULL,
  favourite_snack TEXT, -- Optional: not all penguins have refined palates.
  date_of_birth TIMESTAMP WITH TIME ZONE NOT NULL
);

The row serves 3 purposes:

1. Runtime validation
   Every query that uses sql.type(row) is validated at runtime. If Postgres returns data that doesn’t match this shape, you’ll find out immediately.

2. Static typing
   From this schema, we derive the Row type:

   export type Row = z.infer<typeof row>;

3. Query composition
   The same schema is reused to derive column lists:

   export const columns = Object.keys(row.shape).map((col) =>
     sql.identifier([col]),
   );
   
   export const columnsFragment = sql.join(columns, sql.fragment`, `);

   You will see this used in lots of no-orm’s queries.