Repository vs QueryBuilder vs raw SQL?

Definition:

A repository exposes common operations around an entity, QueryBuilder assembles more flexible database queries, and raw SQL gives direct control over SQL text. These are levels of access rather than a ranking from bad to good. Use the simplest approach that expresses the required query clearly and efficiently.

Key points:

• Repository: common entity reads and writes.

• QueryBuilder: more control over joins, filtering and selected fields.

• Raw SQL: useful for database-specific queries; still use bound parameters.

• Bind values in QueryBuilder and raw SQL; dynamic table or column identifiers need separate allowlists.

Interview point:

• Show how you would inspect the resulting SQL before blaming the ORM for a slow endpoint.