@ElementCollection
@CollectionTable(
    name = "phone_numbers",
    joinColumns = @JoinColumn(name = "user_id"),
    uniqueConstraints = @UniqueConstraint(columnNames = {"user_id", "phone_number"}),
    indexes = @Index(columnList = "phone_number")
)
@Column(name = "phone_number")
private Set<String> phoneNumbers;

import java.util.HashMap;

public class Task170325 {
    public static void main(String[] args) {
        HashMap<String, Integer> map = new HashMap<>();
        map.put(new String("a"), 1);
        map.put(new String("a"), 2);

        System.out.println(map.size());
    }
}

@ElementCollection
@OrderColumn(name = "item_order")
private List<String> items;

@ElementCollection
@CollectionTable(name = "items", joinColumns = @JoinColumn(name = "user_id"))
@OrderColumn(name = "item_order", columnDefinition = "INT NOT NULL")
private List<String> items;

@Entity
@PrimaryKeyJoinColumn(name = "employee_id", referencedColumnName = "id")
public class Employee extends Person {
    // Дополнительные поля и методы
}

@Entity
@PrimaryKeyJoinColumn(
    name = "employee_id",
    referencedColumnName = "id",
    foreignKey = @ForeignKey(name = "fk_employee_person")
)
public class Employee extends Person {
    // Дополнительные поля и методы
}

public class Task180325 {
    public static void main(String[] args) {
        int a = 5;
        double b = 2;
        Long c = (long) (a / b);
        System.out.println(c);
    }
}

@Entity
@Table(name = "employee")
@SecondaryTable(
    name = "employee_details",
    pkJoinColumns = @PrimaryKeyJoinColumn(name = "employee_id")
)
public class Employee {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;

    @Column(table = "employee_details")
    private String address;

    @Column(table = "employee_details")
    private String phoneNumber;

    // Геттеры и сеттеры
}

@Entity
@Table(name = "employee")
@SecondaryTable(
    name = "employee_details",
    pkJoinColumns = @PrimaryKeyJoinColumn(name = "employee_id"),
    uniqueConstraints = @UniqueConstraint(columnNames = {"employee_id", "phoneNumber"}),
    indexes = @Index(columnList = "phoneNumber")
)
public class Employee {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;

    @Column(table = "employee_details")
    private String address;

    @Column(table = "employee_details")
    private String phoneNumber;

    // Геттеры и сеттеры
}

@NamedQuery(
    name = "User.findByEmail",
    query = "SELECT u FROM User u WHERE u.email = :email",
    hints = {
        @QueryHint(name = "org.hibernate.cacheable", value = "true")
    }
)

@NamedQueries({
    @NamedQuery(
        name = "User.findByEmail",
        query = "SELECT u FROM User u WHERE u.email = :email"
    ),
    @NamedQuery(
        name = "User.findAllActive",
        query = "SELECT u FROM User u WHERE u.active = true"
    )
})

spring.jpa.properties.hibernate.cache.use_query_cache=true

@NamedQuery(
    name = "User.findByEmailNative",
    query = "SELECT * FROM users WHERE email = :email",
    resultClass = User.class
)

public interface UserRepository extends JpaRepository<User, Long> {
    @Query("SELECT u FROM User u WHERE u.email = :email")
    User findByEmail(@Param("email") String email);
}