Question

I want to create a table as below:

    BLOCK_USER
    ************
    ID 
    USER_ID, (ID for a single user how want to block other users below)
    USER_ID, (A collection of IDS of users how are going to bee blocked by user above)

It means user A blocking uses B and C and …….

Is possible to do so:

@Entity
@Table(name = "BLOCK_USERS")
public class BlockUsers
{

@Id
@GeneratedValue(strategy = GenerationType.AUTO)
@Column(name = "ID")
private int id;

@OneToMany(cascade=CascadeType.ALL)
@JoinColumn(name="USER_ID")
private User wantToStop_id;

@OneToMany(cascade=CascadeType.ALL)
@JoinColumn(name="USER_ID")
private Collection<User> thoseUsers_ids;

   //getters and setters

 }

Answer 1

You just need a one value in the ‘Blockee’ column, and to create a new row every time A Blocks someone. So:

| ID  |  BlockerID   |   BlockedID  |
|  1  |     5        |       6      |
|  2  |     5        |       7      |
|  3  |     5        |       8      |
|  4  |     5        |      10      |
|  5  |     9        |       5      |

So 5 has blocked 6, 7, 8, 10 and 9 has blocked 5.