Question

我有关于数据库的错误，如下所示： E / CursorWindow（386）：字段槽0的错误请求，-1。 numRows = 1，numColumns = 63

这是我的代码：

公共类DatabaseHandler扩展了SQLiteOpenHelper {

// All Static variables
// Database Version
private static final int DATABASE_VERSION = 1;
// Database Name
private static final String DATABASE_NAME = "contactsManager";
// Contacts table name
private static final String TABLE_CONTACTS = "contacts";
// Contacts Table Columns names
private static final String KEY_ID = "id";
private static final String KEY_IMAGE = "image";
private static final String KEY_NAME = "name";
private static final String KEY_PH_NO = "phone_number";
public DatabaseHandler(Context context) {
    super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
// Creating Tables
@Override
public void onCreate(SQLiteDatabase db) {
    String CREATE_CONTACTS_TABLE = "CREATE TABLE " + TABLE_CONTACTS + "("
            + KEY_ID + " INTEGER PRIMARY KEY,"
            + KEY_IMAGE + " BLOB,"
            + KEY_NAME + " TEXT,"
            + KEY_PH_NO + " TEXT" + ")";
    db.execSQL(CREATE_CONTACTS_TABLE);
}

// Upgrading database
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
    // Drop older table if existed
    db.execSQL("DROP TABLE IF EXISTS " + TABLE_CONTACTS);

    // Create tables again
    onCreate(db);
}

/**
 * All CRUD(Create, Read, Update, Delete) Operations
 */

// Adding new contact
void addContact(Methods contact) {
    SQLiteDatabase db = this.getWritableDatabase();

    ContentValues values = new ContentValues();
    values.put(KEY_IMAGE,contact.getImageId());
    values.put(KEY_NAME, contact.getName()); // Contact Name
    values.put(KEY_PH_NO, contact.getPhoneNumber()); // Contact Phone

    // Inserting Row
    db.insert(TABLE_CONTACTS, null, values);
    db.close(); // Closing database connection
}

// Getting single contact
Methods getContact(int id) {
    SQLiteDatabase db = this.getReadableDatabase();

    Cursor cursor = db.query(TABLE_CONTACTS, new String[] { KEY_ID,KEY_IMAGE,
            KEY_NAME, KEY_PH_NO }, KEY_ID + "=?",
            new String[] { String.valueOf(id) }, null, null, null, null);
    if (cursor != null)
        cursor.moveToFirst();

    Methods contact = new Methods(Integer.parseInt(cursor.getString(cursor.getColumnIndex(KEY_ID))),
            cursor.getBlob(cursor.getColumnIndex(KEY_IMAGE)),cursor.getString(cursor.getColumnIndex(KEY_NAME)), cursor.getString(cursor.getColumnIndex(KEY_PH_NO)));
    // return contact
    cursor.close();
    return contact;
}

// Getting All Contacts
public List<Methods> getAllContacts() {
    List<Methods> contactList = new ArrayList<Methods>();
    // Select All Query
    String selectQuery =  "SELECT  * FROM " + TABLE_CONTACTS;

    SQLiteDatabase db = this.getWritableDatabase();
    Cursor cursor = db.rawQuery(selectQuery, null);

    // looping through all rows and adding to list
    if (cursor.moveToFirst()) {
        do {
            Methods contact = new Methods();
            contact.setID(Integer.parseInt(cursor.getString(0)));
            contact.setImageId(cursor.getBlob(1));
            contact.setName(cursor.getString(2));
            contact.setPhoneNumber(cursor.getString(3));

            // Adding contact to list
            contactList.add(contact);
        } while (cursor.moveToNext());
    }
    cursor.close();
    db.close();
    // return contact list
    return contactList;
}   

/*// Updating single contact
public int updateContact(Methods contact) {
    SQLiteDatabase db = this.getWritableDatabase();

    ContentValues values = new ContentValues();
    values.put(KEY_NAME, contact.getName());
    values.put(KEY_PH_NO, contact.getPhoneNumber());

    // updating row
    return db.update(TABLE_CONTACTS, values, KEY_ID + " = ?",
            new String[] { String.valueOf(contact.getID()) });
}*/

// Deleting single contact
    public void deleteContact(Methods contact) {
        SQLiteDatabase db = this.getWritableDatabase();
        db.delete(TABLE_CONTACTS, KEY_ID + " = ?",
                new String[] { String.valueOf(contact.getID()) });
        db.close();
        Log.v("deleteContact", "Deleted row is:  "+String.valueOf(contact.getID()));
    }   

void deleteAll(Methods contact)
{
    SQLiteDatabase db= this.getWritableDatabase();
    db.delete(TABLE_CONTACTS, null, null);
    db.close();

}
// Getting contacts Count
public int getContactsCount() {
    String countQuery = "SELECT  * FROM " + TABLE_CONTACTS;
    SQLiteDatabase db = this.getReadableDatabase();
    Cursor cursor = db.rawQuery(countQuery, null);
    cursor.close();

    // return count
    return cursor.getCount();
}

}

Answer 1

在这里获取更多信息会有所帮助（也许是堆栈跟踪？）。但是，添加联系人时似乎没有提供“id”。请考虑使此列自动递增。

最后，如果这是一个Android问题，您的主键列应该是自动递增的，应该称为“_id”，否则请确保在查询返回的任何游标中将其作为列名提供。还要检查您的数据库是否也有一个名为“android_metadata”的表。

连接到databasehandler时出错

1 个答案: