Question

我有2个表Employee和order表，我试图将这些表实现到同一个databasehelper类中，但是这给了我几个错误，应该创建另一个databasehelper类，还是可以将它们实现为一个< / p>

表看起来像这样公共类DatabaseHelper扩展了SQLiteOpenHelper {

    private static final String DB_NAME = "shopinstyle.db";
    private static final String DB_TABLE = "Employee";
    private static final String ORDER_TABLE = "Order";

    //Employee
    //columns
    private static final String ID = "ID";
    private static final String FNAME = "FNAME";
    private static final String LNAME = "LNAME";
    private static final String PNUMBER = "PNUMBER";
    private static final String EMAIL = "EMAIL";
    private static final String NIC = "NIC";

    //Order
    //columns
    private static final String ord_ID = "ord_ID";
    private static final String ord_Name = "ord_Name";
    private static final String ord_Qty = "ord_Qty";
    private static final String ord_Price = "ord_Price";
    private static final String ord_Location = "ord_Location";

    private static final String CREATE_TABLE = "CREATE TABLE " + DB_TABLE + " (" +
            ID + " INTEGER PRIMARY KEY AUTOINCREMENT, " +
            FNAME + " TEXT, " +
            LNAME + " TEXT, " +
            PNUMBER + " TEXT, " +
            EMAIL + " TEXT, " +
            NIC + " TEXT" + ")";

    private static final String CREATE_TABLE_ORDER = "CREATE TABLE " + ORDER_TABLE + " (" +
            ord_ID + " INTEGER PRIMARY KEY AUTOINCREMENT, " +
            ord_Name + " TEXT, " +
            ord_Qty + " TEXT, " +
            ord_Price + " TEXT, " +
            ord_Location + " TEXT " + ")";

    public DatabaseHelper(Context context) {
        super(context, DB_NAME,ORDER_TABLE, null, 1);
    }

    @Override
    public void onCreate(SQLiteDatabase sqLiteDatabase) {

        sqLiteDatabase.execSQL(CREATE_TABLE);
        sqLiteDatabase.execSQL(CREATE_TABLE_ORDER);
    }

    @Override
    public void onUpgrade(SQLiteDatabase sqLiteDatabase, int i, int i1) {

        sqLiteDatabase.execSQL("DROP TABLE IF EXISTS " + DB_TABLE);
        sqLiteDatabase.execSQL("DROP TABLE IF EXISTS " + ORDER_TABLE);
        onCreate(sqLiteDatabase);

    }`

此行有错误

public DatabaseHelper(Context context) {
    super(context, DB_NAME,ORDER_TABLE, null, 1);
}

Answer 1

super()类的构造函数中DatabaseHelper的cal中的3d参数是factory，您可以将其作为null而不是表的名称进行传递：

super(context, DB_NAME,null, 1);

在一个databasehelper类中添加多个表

1 个答案: