To update multiple fields in DB with JPA you have to use @Modifying and @Query. Here, an example:
@Repository
public interface CarRepository extends JpaRepository<CarDto, String> {
//Here we update fields color and brand dynamically using parameters
@Modifying
@Query("update CarDto c set c.color = :color, c.brand = :brand where c.numberOfDoors = 5")
void updateColorAndBrand(@Param("color") String color, @Param("brand") String brand);
}
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