supabase-cli/docs/supabase/db/reset.md

supabase-db-reset

Resets the local database to a clean state.

Requires the local development stack to be started by running supabase start.

Recreates the local Postgres container and applies all local migrations found in supabase/migrations directory. If test data is defined in supabase/seed.sql, it will be seeded after the migrations are run. Any other data or schema changes made during local development will be discarded.

When running db reset with --linked or --db-url flag, a SQL script is executed to identify and drop all user created entities in the remote database. Since Postgres roles are cluster level entities, any custom roles created through the dashboard or supabase/roles.sql will not be deleted by remote reset.