Declarative schema migrations offer a streamlined approach to managing database changes by using configuration files that can be easily modified and applied through command-line interface tools, similar to Infrastructure as Code (IaC) practices. This method provides several benefits, including a single source of truth for the schema, ease of understanding for developers unfamiliar with Data Definition Language (DDL), and simplified automation within continuous deployment processes. However, it also presents challenges such as potential conflicts from simultaneous changes by multiple developers and the inherent statefulness of databases that necessitates careful handling to avoid unintended data impacts. In environments like PlanetScale, a branching strategy can be employed to safely manage schema changes, allowing developers to create working branches for modifications and utilize dedicated repositories to track schema definition changes, which can then be reviewed and applied to production branches through controlled deploy requests.