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Android 从intent获取sqlite(聚合)和_Android_Android Sqlite_Aggregate - Fatal编程技术网

Android 从intent获取sqlite(聚合)和

Android 从intent获取sqlite(聚合)和,android,android-sqlite,aggregate,Android,Android Sqlite,Aggregate,我对android非常陌生,我只想请求一些帮助,从我的数据库中获取数据的总和,我使用date进行筛选,然后它将显示总数,非常感谢,这是我的 EOperation.java public DailyExpense getSumE(String date){ Cursor cursor = database.rawQuery("SELECT SUM(" + (EdailyHandler.COLUMN_AMOUNT) + ") FROM " + EdailyHandler.TABLE_DAIL

我对android非常陌生,我只想请求一些帮助,从我的数据库中获取数据的总和,我使用date进行筛选,然后它将显示总数,非常感谢,这是我的 EOperation.java

public DailyExpense getSumE(String date){
    Cursor cursor = database.rawQuery("SELECT SUM(" + (EdailyHandler.COLUMN_AMOUNT) + ") FROM " + EdailyHandler.TABLE_DAILY + "WHERE " + EdailyHandler.COLUMN_DATE +"=?",new String[]{String.valueOf(date)}, null);

  if(cursor.getCount() > 0)
        cursor.moveToFirst();
    while(cursor.moveToNext()){
        expense = new DailyExpense(Long.parseLong(cursor.getString(0)),cursor.getString(1), Float.parseFloat(cursor.getString(2)), cursor.getString(3), cursor.getString(4));

    }


    return expense;
}
显然,它将显示数据库中的总数
但是ut没有显示任何内容

您如何在数据库中存储日期?指定的日期是什么?而且,您的SELECT只是一个SUM,那么为什么您的游标超过了
。getLong(0)
?0相当于id,下面是datamodel>公共类DailyExpense{`private Long Eid;private String date;private Float amount;private String type;private String comment;`Java模型并不重要。游标只返回一列,因为这是您告诉它的