Inserting a foreign key into a table

问题:

How to insert foreign key into a table? I have two table (Info and WorkDetails) where WorkDetails has a foreign key which refer to Info. Is this the correct way to implement?

MyDatabaseHelper.java

 public void onCreate(SQLiteDatabase db)
    {
       db.execSQL("create table "+TABLE_INFO+"(ID INTEGER PRIMARY KEY ,Name TEXT,Weather TEXT, Date DATETIME, Status Text)");
       db.execSQL("create table"+TABLE_WORKDETAILS+"(ID INTEGER PRIMARY KEY , Project TEXT, WorkDescription TEXT, Per Text, TimeIn DATETIME, TimeOut DATETIME,TotalHours DATETIME, TableInfo_id INTEGER, FOREIGN KEY(TableInfo_id)REFERENCES TABLE_INFO(ID)");
    }

WorkDetailsAPI.java

public class WorkDetailsAPI {
    private SQLiteDatabase database;
    private MyDatabaseHelper dbHelper;
    public String[] allColumns={MyDatabaseHelper.ID2,MyDatabaseHelper.Project,MyDatabaseHelper.WorkDescription,MyDatabaseHelper.Per,MyDatabaseHelper.TimeIn,MyDatabaseHelper.TimeOut,MyDatabaseHelper.TotalHours,MyDatabaseHelper.TableInfo_id};

    public WorkDetailsAPI(Context context)
                   ....
    public long insertWorkDetails(String project, String workDescription, String per,String timeIn,String timeOut,String totalHours)
    {
        database=dbHelper.getWritableDatabase();
        ContentValues values=new ContentValues();
        values.put(MyDatabaseHelper.Project,project);
        values.put(MyDatabaseHelper.WorkDescription,workDescription);
        values.put(MyDatabaseHelper.Per,per);
        values.put(MyDatabaseHelper.TimeIn,timeIn);
        values.put(MyDatabaseHelper.TimeOut,timeOut);
        values.put(MyDatabaseHelper.TotalHours,totalHours);
        database.insert(MyDatabaseHelper.TABLE_WORKDETAILS,null,values);
        database.close();
        return 0 ;

    }

}

WorkDetails.java

public void add() {
    button.setOnClickListener
        .....
            TI.insertTableInfo(name,weather,date,status);
            WD.insertWorkDetails(a,b,c,d,e,f); // Do I need to include the foreign key?
}

回答1:

Yes you're doing it the right way