每日总结

1.今天继续学习SQLLITE

修改数据：

public void update(Person p)
{
    SQLiteDatabase db = dbOpenHelper.getWritableDatabase();
    db.execSQL("UPDATE person SET name = ?,phone = ? WHERE personid = ?",
        new String[]{p.getName(),p.getPhone(),p.getId()});
}

查询数据：

public Person find(Integer id)
{
    SQLiteDatabase db = dbOpenHelper.getReadableDatabase();
    Cursor cursor =  db.rawQuery("SELECT * FROM person WHERE personid = ?",
            new String[]{id.toString()});
    //存在数据才返回true
    if(cursor.moveToFirst())
    {
        int personid = cursor.getInt(cursor.getColumnIndex("personid"));
        String name = cursor.getString(cursor.getColumnIndex("name"));
        String phone = cursor.getString(cursor.getColumnIndex("phone"));
        return new Person(personid,name,phone);
    }
    cursor.close();
    return null;
}