ValueError：<too many =“”values =“”to =“”unpack =“”> </too>

Question

任务是查找，排序和删除学生的类型＆＃39;：＆＃34; homework＆＃34;并使用MongoDB获得最低分。我也尝试使用toArray()函数，但它给出了一个错误。现在我尝试将文档作为一些计数器移动，并删除分数最低的最后一个排序文档。

import pymongo 
import sys       

#establish a connection to the database
connection = pymongo.MongoClient("mongodb://localhost")

def delete_lowest_doc():

    #get a handle to the students database
    db=connection.students
    grades = db.grades


    try:
        for i in range(0,grades.find().count()):
            docs_1 = grades.find({'type':"homework", 'student_id':i}).sort(['score',-1])

            counter_1 = grades.find({'type':"homework",'student_id':i})
            counter_2 = counter_1.sort(['score',-1]).count() 

            while (counter_2>0):
                doc = docs_1.next();
                counter_2=counter_2-1;
            grades.remove(doc)


    except Exception as e:
        print ("Unexpected error:", type(e), e)

delete_lowest_doc()

Answer 1

collection.find只需要一个位置参数，你就会给它两个。

更改您的通话，使它们如下所示：grades.find({"type": "homework", "student_id": i})。