從SQLite獲取所有行

Question

我一直試圖從SQLite數據庫獲取所有行。但是，我只從下面的代碼中得到最後一行。

文件選擇器類：

public ArrayList<String> readFileFromSQLite() { 

    fileName = new ArrayList<String>(); 

    fileSQLiteAdapter = new FileSQLiteAdapter(FileChooser.this); 
    fileSQLiteAdapter.openToRead(); 
    cursor = fileSQLiteAdapter.queueAll(); 

    if (cursor != null) { 
    if (cursor.moveToFirst()) { 
     do { 
     fileName.add(cursor.getString(cursor.getColumnIndex(FileSQLiteAdapter.KEY_CONTENT1))); 
     } while (cursor.moveToNext()); 

    } 
    cursor.close(); 
    } 

    fileSQLiteAdapter.close(); 
    return fileName; 
} 

FileSQLiteAdapter類：

public Cursor queueAll() { 
    String[] columns = new String[] { KEY_ID, KEY_CONTENT1 }; 

    Cursor cursor = sqLiteDatabase.query(MYDATABASE_TABLE, columns, null, 
       null, null, null, null); 
    return cursor; 
} 

請告訴我哪裏是我的不正確。欣賞。

Answer 1

嘗試：

Cursor cursor = db.rawQuery("select * from table",null); 

和List<String>：

if (cursor.moveToFirst()) { 
    while (!cursor.isAfterLast()) { 
    String name = cursor.getString(cursor.getColumnIndex(countyname)); 

    list.add(name); 
    cursor.moveToNext(); 
    } 
} 

Answer 2

我一直在尋找到同樣的問題！我認爲你的問題與你在哪裏識別你用來填充你返回的ArrayList的變量有關。如果您在循環中定義它，那麼它將始終引用數據庫中表中的最後一行。爲了避免這種情況，你必須確定它的外循環：

String name; 
if (cursor.moveToFirst()) { 

     while (cursor.isAfterLast() == false) { 
      name = cursor.getString(cursor 
        .getColumnIndex(countyname)); 

      list.add(name); 
      cursor.moveToNext(); 
     } 
} 

Answer 3

這幾乎是相同的解決方案爲別人，但我想這可能是很好看實現相同的結果的不同方式，解釋一下：

大概你有表名字符串變量在你調用DBHandler的時候被初始化，所以它會是這樣的;

private static final String MYDATABASE_TABLE = "anyTableName"; 

然後，無論您嘗試檢索所有表格行，

SQLiteDatabase db = this.getReadableDatabase(); 
Cursor cursor = db.rawQuery("select * from " + MYDATABASE_TABLE, null); 

List<String> fileName = new ArrayList<>(); 
if (cursor.moveToFirst()){ 
    fileName.add(cursor.getString(cursor.getColumnIndex(COLUMN_NAME))); 
    while(cursor.moveToNext()){ 
     fileName.add(cursor.getString(cursor.getColumnIndex(COLUMN_NAME))); 
    } 
} 
cursor.close(); 
db.close(); 

老實說，大概有這樣做的方法很多，

Answer 4

更新queueAll()方法如下：

更新readFileFromSQLite()方法如下：

public ArrayList<String> readFileFromSQLite() { 

    fileName = new ArrayList<String>(); 

    fileSQLiteAdapter = new FileSQLiteAdapter(FileChooser.this); 
    fileSQLiteAdapter.openToRead(); 

    cursor = fileSQLiteAdapter.queueAll(); 

    if (cursor != null) { 
     if (cursor.moveToFirst()) { 
      do 
      { 
       String name = cursor.getString(cursor.getColumnIndex(FileSQLiteAdapter.KEY_CONTENT1)); 
       fileName.add(name); 
      } while (cursor.moveToNext()); 
     } 
     cursor.close(); 
    } 

    fileSQLiteAdapter.close(); 

    return fileName; 
} 

Answer 5

其他答案使用rawQuery。 documentation對於SQLiteDatabase表示，您可以將null傳遞給查詢的selection參數以獲取所有行。

selection傳遞null將返回給定表的所有行。

例

SQLiteDatabase db = mHelper.getReadableDatabase(); 
String[] columns = { 
     MyDatabaseHelper.COLUMN_1, 
     MyDatabaseHelper.COLUMN_2, 
     MyDatabaseHelper.COLUMN_3}; 
String selection = null; // this will select all rows 
Cursor cursor = db.query(MyDatabaseHelper.MY_TABLE, columns, selection, 
     null, null, null, null, null); 

Answer 6

Cursor cursor = myDb.viewData(); 

     if (cursor.moveToFirst()){ 
       do { 
       String itemname=cursor.getString(cursor.getColumnIndex(myDb.col_2)); 
       String price=cursor.getString(cursor.getColumnIndex(myDb.col_3)); 
       String quantity=cursor.getString(cursor.getColumnIndex(myDb.col_4)); 
       String table_no=cursor.getString(cursor.getColumnIndex(myDb.col_5)); 

       }while (cursor.moveToNext()); 

       } 

       cursor.requery();