each table has only one Primary Key

[Jayin]

bug like:

class Student extends Human {
    @PrimaryKey
    long id;

    int age;

    String name;

    List<Integer> friendid;

    public long getId() {
        return id;
    }

    public void setId(long id) {
        this.id = id;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public List<Integer> getFriendid() {
        return friendid;
    }

    public void setFriendid(List<Integer> friendid) {
        this.friendid = friendid;
    }

}

class Human extends Model {

    int height;

    int wight;

    public int getHeight() {
        return height;
    }

    public void setHeight(int height) {
        this.height = height;
    }

    public int getWight() {
        return wight;
    }

    public void setWight(int wight) {
        this.wight = wight;
    }

}

the sql below is incorrect

Create Table Student (name TEXT ,id INTEGER Primary Key AUTOINCREMENT,age INTEGER ,height INTEGER ,wight INTEGER ,__id INTEGER Primary Key AUTOINCREMENT)

typically,we are support to follow the user ---- remove the __id

[Jayin]

Solution 1

firstly,we should controll the user action:
If the @PrimaryKey keeps opening,it may cause some confuse to some users who not very fimiliar to database :we can define one more Primary Key in one table.

so,I will remove it.

1.default @table(name="tablename",id="__id")

• id means the PRIMARY KEY AUTOINCREMENT
• motify the id to custom you primar key

2.When saving and delete the model,take care of the id

Solution 2

Solution 1 looks nice,but it's hard to code.Every time you save or delete,you have to figure out the where the id is.

to be lazy is:
Not able to give a right to user to motify the id

[Jayin]

use @unique instead of @PrimaryKey