The structure that describes how data is organized: tables, fields, their types and the relationships between them.
A data schema is the blueprint of a database. It specifies, for example, that the orders table has an order number, customer, amount, status and date, that each order belongs to one customer and that the amount is a number, not text. A good schema keeps data consistent and easy to use.
Changing the schema after the database fills up is harder than designing it well at the start. A poor schema causes duplicated data, wrong reports and slow performance. That is why smart builders usually review the schema before building screens.
Practical tip: review the schema AI proposes in plain terms: does every important piece of information have a home, and is there a phone field in international format? When changing the schema of a live app, apply the change in staging first, with a backup.