英文:
Android SQLITE foreign key column is null
问题
项目包含2个表，一个是Duser，包含所有用户信息；第二个是test表。我想要将用户的ID（在Duser表中作为主键）作为外键传递到test表中。但当我打开数据库时，外键列总是为空。我已经使用pragma启用了外键，我需要手动传递外键还是SQLite会自动处理？如果需要手动处理，该怎么做？请帮忙。
@Override
public void onCreate(SQLiteDatabase sqLiteDatabase) {
sqLiteDatabase.execSQL("CREATE TABLE Duser(id INTEGER PRIMARY KEY AUTOINCREMENT, email TEXT, name TEXT, password TEXT, confirm TEXT, number TEXT)");
sqLiteDatabase.execSQL("CREATE TABLE test(Iid INTEGER PRIMARY KEY AUTOINCREMENT, name TEXT, f_id INTEGER NOT NULL, FOREIGN KEY(f_id) REFERENCES Duser(id) ON UPDATE RESTRICT ON DELETE RESTRICT)");
onConfigure(sqLiteDatabase);
}
@Override
public void onConfigure(SQLiteDatabase db) {
super.onConfigure(db);
db.execSQL("PRAGMA foreign_keys=ON;");
}
public boolean Insert(String email, String name, String password, String confirm, String number) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues contentValues = new ContentValues();
contentValues.put("email", email);
contentValues.put("name", name);
contentValues.put("password", password);
contentValues.put("confirm", confirm);
contentValues.put("number", number);
long ins = db.insert("Duser", null, contentValues);
return ins != -1;
}
public boolean addInterest(String name) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues contentValues = new ContentValues();
contentValues.put("name", name);
long ins = db.insert("test", null, contentValues);
return ins != -1;
}
英文:
The project contains 2 tables one is Duser which contains all the user information and the second one is the test table. I want to pass the User's id which is the primary key in Duser Table as a foreign key in the test table. when I'm opening the database foreign key column is always null. I have also enabled foreign-key by using pragrma, Do I need to pass foreign key manually or SQLite will do it? if manually then how? Please help.
@Override
public void onCreate(SQLiteDatabase sqLiteDatabase) {
sqLiteDatabase.execSQL("Create Table Duser(id integer primary key autoincrement,email Text, name text,password text, confirm text, number string)");
sqLiteDatabase.execSQL("Create table test(Iid integer primary key autoincrement, name Text, f_id integer NOT NULL , Foreign key(f_id) REFERENCES DUSER(id) on update restrict on delete restrict)");
onConfigure(sqLiteDatabase);
}
@Override
public void onConfigure(SQLiteDatabase db) {
super.onConfigure(db);
db.execSQL("PRAGMA foreign_keys=ON;");
}
public boolean Insert(String email, String name, String password, String confirm, String number) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues contentValues = new ContentValues();
contentValues.put("email", email);
contentValues.put("name", name);
contentValues.put("password", password);
contentValues.put("confirm", confirm);
contentValues.put("number", number);
long ins = db.insert("Duser", "null", contentValues);
if (ins == -1)
return false;
else return true;
}
public boolean addInterest(String name) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues contentValues = new ContentValues();
contentValues.put("name", name);
long ins = db.insert("test", null, contentValues);
if (ins == -1)
return false;
else return true;
}
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