@Entity
@Table(name = "products")
public class Product {
    
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;
    
    @Column(nullable = false)
    private String name;
    
    @Column
    private String description;
    
    @Column(precision = 10, scale = 2)
    private BigDecimal price;
    
    // Constructors, getters, and setters
    public Product() {}
    
    public Product(String name, String description, BigDecimal price) {
        this.name = name;
        this.description = description;
        this.price = price;
    }
    
    // Getters and setters...
}

@Repository
public interface ProductRepository extends JpaRepository<Product, Long> {
    
    // Derived query methods
    List<Product> findByNameContaining(String name);
    
    List<Product> findByPriceBetween(BigDecimal minPrice, BigDecimal maxPrice);
    
    // Custom JPQL query
    @Query("SELECT p FROM Product p WHERE p.price > :minPrice")
    List<Product> findExpensiveProducts(@Param("minPrice") BigDecimal minPrice);
    
    // Native SQL query
    @Query(value = "SELECT * FROM products ORDER BY price DESC LIMIT 5", nativeQuery = true)
    List<Product> findTop5ExpensiveProducts();
}