Python MongoDB执行查询

我有MongoDB的疑问：

mongo_query = db.transacciones.aggregate( 
{
    $project : 
    { 
        month : {$month : "$day"}, 
        year : {$year :  "$day"},
        pr_avg_rate : 1,
        pr_avg_rate_approved : 1,
        pr_numbers : 1,
        pr_numbers_approved : 1,
        pr_total_amount : 1,
        pr_total_amount_approved : 1      
    }
}, 
{
    $group : { 
        _id : {month : "$month" ,year : "$year" },
        pr_avg_rate : {$avg : "$pr_avg_rate"},
        pr_avg_rate_approved : {$avg : "$pr_avg_rate_approved"},
        pr_numbers : {$sum : "$pr_numbers"},
        pr_numbers_approved : {$sum : "$pr_numbers_approved"},
        pr_total_amount : {$sum : "$pr_total_amount"},
        pr_total_amount_approved : {$sum : "$pr_total_amount_approved"} 
    }
})

我正在尝试使用Pymongo执行，但不起作用，错误是：

Error: connection not established pipeline must be a list

完成该工作的功能是：

def execute_agregation(self, query, collection_name):
    result = None
    try:
        collection = self._instance.db[collection_name]
        result = collection.aggregate(query)
        print(result)
    except Exception as error:
        print('Error: connection not established {}'.format(error))
        return None
    else:
        return result

在下一条指令中调用：

result = mongo_conn.execute_agregation(mongo_query, "transacciones")

---

mongo_conn是一个名为mongo的类的实例。

您的聚合管道需要设置为一个阶段列表。因此，在JSON中使用方括号表示数组

mongo_query = db.transacciones.aggregate([ 
{
    $project : 
    { 
        month : {$month : "$day"}, 
        year : {$year :  "$day"},
        pr_avg_rate : 1,
        pr_avg_rate_approved : 1,
        pr_numbers : 1,
        pr_numbers_approved : 1,
        pr_total_amount : 1,
        pr_total_amount_approved : 1      
    }
}, 
{
    $group : { 
        _id : {month : "$month" ,year : "$year" },
        pr_avg_rate : {$avg : "$pr_avg_rate"},
        pr_avg_rate_approved : {$avg : "$pr_avg_rate_approved"},
        pr_numbers : {$sum : "$pr_numbers"},
        pr_numbers_approved : {$sum : "$pr_numbers_approved"},
        pr_total_amount : {$sum : "$pr_total_amount"},
        pr_total_amount_approved : {$sum : "$pr_total_amount_approved"} 
    }
}
])

---

需要将聚合管道设置为阶段列表。因此，在JSON中使用方括号表示数组

mongo_query = db.transacciones.aggregate([ 
{
    $project : 
    { 
        month : {$month : "$day"}, 
        year : {$year :  "$day"},
        pr_avg_rate : 1,
        pr_avg_rate_approved : 1,
        pr_numbers : 1,
        pr_numbers_approved : 1,
        pr_total_amount : 1,
        pr_total_amount_approved : 1      
    }
}, 
{
    $group : { 
        _id : {month : "$month" ,year : "$year" },
        pr_avg_rate : {$avg : "$pr_avg_rate"},
        pr_avg_rate_approved : {$avg : "$pr_avg_rate_approved"},
        pr_numbers : {$sum : "$pr_numbers"},
        pr_numbers_approved : {$sum : "$pr_numbers_approved"},
        pr_total_amount : {$sum : "$pr_total_amount"},
        pr_total_amount_approved : {$sum : "$pr_total_amount_approved"} 
    }
}
])

---

我认为这里有两个问题 1.我们需要按照@Mahesh Nayak的建议，使用方括号将骨料管道定义为阶段

mongo_query = db.transacciones.aggregate([
{
    $project : 
    { 
        month : {$month : "$day"}, 
        year : {$year :  "$day"},
        pr_avg_rate : 1,
        pr_avg_rate_approved : 1,
        pr_numbers : 1,
        pr_numbers_approved : 1,
        pr_total_amount : 1,
        pr_total_amount_approved : 1      
    }
}, 
{
    $group : { 
        _id : {month : "$month" ,year : "$year" },
        pr_avg_rate : {$avg : "$pr_avg_rate"},
        pr_avg_rate_approved : {$avg : "$pr_avg_rate_approved"},
        pr_numbers : {$sum : "$pr_numbers"},
        pr_numbers_approved : {$sum : "$pr_numbers_approved"},
        pr_total_amount : {$sum : "$pr_total_amount"},
        pr_total_amount_approved : {$sum : "$pr_total_amount_approved"} 
    }
}])

函数的第二个问题是您正在传递集合名称和查询，但查询已经是mongodb游标

或者您必须按照以下方式修改您的查询

query = [
{
    $project : 
    { 
        month : {$month : "$day"}, 
        year : {$year :  "$day"},
        pr_avg_rate : 1,
        pr_avg_rate_approved : 1,
        pr_numbers : 1,
        pr_numbers_approved : 1,
        pr_total_amount : 1,
        pr_total_amount_approved : 1      
    }
}, 
{
    $group : { 
        _id : {month : "$month" ,year : "$year" },
        pr_avg_rate : {$avg : "$pr_avg_rate"},
        pr_avg_rate_approved : {$avg : "$pr_avg_rate_approved"},
        pr_numbers : {$sum : "$pr_numbers"},
        pr_numbers_approved : {$sum : "$pr_numbers_approved"},
        pr_total_amount : {$sum : "$pr_total_amount"},
        pr_total_amount_approved : {$sum : "$pr_total_amount_approved"} 
    }
}]

#Or modify your function as below 
def execute_agregation(self, query):
    result = None
    try:
        result = query
        print(result)
    except Exception as error:
        print('Error: connection not established {}'.format(error))
        return None
    else:
        return result

---

我认为这里有两个问题 1.我们需要按照@Mahesh Nayak的建议，使用方括号将骨料管道定义为阶段

mongo_query = db.transacciones.aggregate([
{
    $project : 
    { 
        month : {$month : "$day"}, 
        year : {$year :  "$day"},
        pr_avg_rate : 1,
        pr_avg_rate_approved : 1,
        pr_numbers : 1,
        pr_numbers_approved : 1,
        pr_total_amount : 1,
        pr_total_amount_approved : 1      
    }
}, 
{
    $group : { 
        _id : {month : "$month" ,year : "$year" },
        pr_avg_rate : {$avg : "$pr_avg_rate"},
        pr_avg_rate_approved : {$avg : "$pr_avg_rate_approved"},
        pr_numbers : {$sum : "$pr_numbers"},
        pr_numbers_approved : {$sum : "$pr_numbers_approved"},
        pr_total_amount : {$sum : "$pr_total_amount"},
        pr_total_amount_approved : {$sum : "$pr_total_amount_approved"} 
    }
}])

函数的第二个问题是您正在传递集合名称和查询，但查询已经是mongodb游标

或者您必须按照以下方式修改您的查询

query = [
{
    $project : 
    { 
        month : {$month : "$day"}, 
        year : {$year :  "$day"},
        pr_avg_rate : 1,
        pr_avg_rate_approved : 1,
        pr_numbers : 1,
        pr_numbers_approved : 1,
        pr_total_amount : 1,
        pr_total_amount_approved : 1      
    }
}, 
{
    $group : { 
        _id : {month : "$month" ,year : "$year" },
        pr_avg_rate : {$avg : "$pr_avg_rate"},
        pr_avg_rate_approved : {$avg : "$pr_avg_rate_approved"},
        pr_numbers : {$sum : "$pr_numbers"},
        pr_numbers_approved : {$sum : "$pr_numbers_approved"},
        pr_total_amount : {$sum : "$pr_total_amount"},
        pr_total_amount_approved : {$sum : "$pr_total_amount_approved"} 
    }
}]

#Or modify your function as below 
def execute_agregation(self, query):
    result = None
    try:
        result = query
        print(result)
    except Exception as error:
        print('Error: connection not established {}'.format(error))
        return None
    else:
        return result

由于和，我得到了函数执行\u agregion的近似解：

def execute_agregation(self, query, collection_name):
    result = None
    try:
        collection = self._instance.db[collection_name]
        pipeline = [
            {
                "$project" : 
                { 
                    "month" : {"$month" : "$day"}, 
                    "year" : {"$year" :  "$day"},
                    "pr_avg_rate" : 1,
                    "pr_avg_rate_approved" : 1,
                    "pr_numbers" : 1,
                    "pr_numbers_approved" : 1,
                    "pr_total_amount" : 1,
                    "pr_total_amount_approved" : 1      
                }
            }, 
            {
                "$group" : { 
                    "_id" : {"month" : "$month" ,"year" : "$year" },
                    "pr_avg_rate" : {"$avg" : "$pr_avg_rate"},
                    "pr_avg_rate_approved" : {"$avg" : "$pr_avg_rate_approved"},
                    "pr_numbers" : {"$sum" : "$pr_numbers"},
                    "pr_numbers_approved" : {"$sum" : "$pr_numbers_approved"},
                    "pr_total_amount" : {"$sum" : "$pr_total_amount"},
                    "pr_total_amount_approved" : {"$sum" : "$pr_total_amount_approved"} 
                }
            }
        ]
        # print(pipeline)
        result = collection.aggregate(pipeline)
        # print(result)
    except Exception as error:
        print('Error: connection not established {}'.format(error))
        return None
    else:
        return result

但现在，我尝试使用名为query的变量，它是一个具有以下结构的字符串：

"{'$project': {'month': {'$month': '$day'}, 'year': {'$year': '$day'}, 'pr_avg_rate': 1, 'pr_avg_rate_approved': 1, 'pr_numbers': 1, 'pr_numbers_approved': 1, 'pr_total_amount': 1, 'pr_total_amount_approved': 1}}, {'$group': {'_id': {'month': '$month', 'year': '$year'}, 'pr_avg_rate': {'$avg': '$pr_avg_rate'}, 'pr_avg_rate_approved': {'$avg': '$pr_avg_rate_approved'}, 'pr_numbers': {'$sum': '$pr_numbers'}, 'pr_numbers_approved': {'$sum': '$pr_numbers_approved'}, 'pr_total_amount': {'$sum': '$pr_total_amount'}, 'pr_total_amount_approved': {'$sum': '$pr_total_amount_approved'}}}"

我想把查询放在管道数组中，就像

pipeline = [query]

但是它现在不起作用，在这种情况下。

多亏了和，我得到了函数的近似解执行\u agregion：

def execute_agregation(self, query, collection_name):
    result = None
    try:
        collection = self._instance.db[collection_name]
        pipeline = [
            {
                "$project" : 
                { 
                    "month" : {"$month" : "$day"}, 
                    "year" : {"$year" :  "$day"},
                    "pr_avg_rate" : 1,
                    "pr_avg_rate_approved" : 1,
                    "pr_numbers" : 1,
                    "pr_numbers_approved" : 1,
                    "pr_total_amount" : 1,
                    "pr_total_amount_approved" : 1      
                }
            }, 
            {
                "$group" : { 
                    "_id" : {"month" : "$month" ,"year" : "$year" },
                    "pr_avg_rate" : {"$avg" : "$pr_avg_rate"},
                    "pr_avg_rate_approved" : {"$avg" : "$pr_avg_rate_approved"},
                    "pr_numbers" : {"$sum" : "$pr_numbers"},
                    "pr_numbers_approved" : {"$sum" : "$pr_numbers_approved"},
                    "pr_total_amount" : {"$sum" : "$pr_total_amount"},
                    "pr_total_amount_approved" : {"$sum" : "$pr_total_amount_approved"} 
                }
            }
        ]
        # print(pipeline)
        result = collection.aggregate(pipeline)
        # print(result)
    except Exception as error:
        print('Error: connection not established {}'.format(error))
        return None
    else:
        return result

但现在，我尝试使用名为query的变量，它是一个具有以下结构的字符串：

"{'$project': {'month': {'$month': '$day'}, 'year': {'$year': '$day'}, 'pr_avg_rate': 1, 'pr_avg_rate_approved': 1, 'pr_numbers': 1, 'pr_numbers_approved': 1, 'pr_total_amount': 1, 'pr_total_amount_approved': 1}}, {'$group': {'_id': {'month': '$month', 'year': '$year'}, 'pr_avg_rate': {'$avg': '$pr_avg_rate'}, 'pr_avg_rate_approved': {'$avg': '$pr_avg_rate_approved'}, 'pr_numbers': {'$sum': '$pr_numbers'}, 'pr_numbers_approved': {'$sum': '$pr_numbers_approved'}, 'pr_total_amount': {'$sum': '$pr_total_amount'}, 'pr_total_amount_approved': {'$sum': '$pr_total_amount_approved'}}}"

我想把查询放在管道数组中，就像

pipeline = [query]

但是现在不行，就这样