mongodb-$sum返回0
此查询的目的是在“为员工报税表提供销售总数”时进行 我的第一个问题是mongodb-$sum返回0,mongodb,mongodb-query,aggregation-framework,Mongodb,Mongodb Query,Aggregation Framework,此查询的目的是在“为员工报税表提供销售总数”时进行 我的第一个问题是 db.Employee.aggregate([{$lookup: {from: "Invoice", localField: "_id", foreignField: "_id", as: "Invoices"}}, {$match: {_id: 2}}]).pretty() 它返回了下面的代码段,尽管该员工有多个客户,但它只返回一个客户。我不太清楚为什么它只返回一个 { "_id" : 2, "LastName" : "E
db.Employee.aggregate([{$lookup: {from: "Invoice", localField: "_id", foreignField: "_id", as: "Invoices"}}, {$match: {_id: 2}}]).pretty()
它返回了下面的代码段,尽管该员工有多个客户,但它只返回一个客户。我不太清楚为什么它只返回一个
{
"_id" : 2,
"LastName" : "Edwards",
"FirstName" : "Nancy",
"Title" : "Sales Manager",
"ReportsTo" : 1,
"BirthDate" : ISODate("1958-12-08T00:00:00Z"),
"HireDate" : ISODate("2002-05-01T00:00:00Z"),
"Address" : "825 8 Ave SW",
"City" : "Calgary",
"State" : "AB",
"Country" : "Canada",
"PostalCode" : "T2P 2T3",
"Phone" : "+1 (403) 262-3443",
"Fax" : "+1 (403) 262-3322",
"Email" : "nancy@chinookcorp.com",
"Invoices" : [
{
"_id" : 2,
"CustomerId" : 4,
"InvoiceDate" : ISODate("2009-01-02T00:00:00Z"),
"BillingAddress" : "Ullevålsveien 14",
"BillingCity" : "Oslo",
"BillingState" : null,
"BillingCountry" : "Norway",
"BillingPostalCode" : "0171",
"Total" : 3.96,
"InvoiceLines" : [
{
"_id" : 3,
"TrackId" : 6,
"UnitPrice" : 0.99,
"Quantity" : 1
},
{
"_id" : 4,
"TrackId" : 8,
"UnitPrice" : 0.99,
"Quantity" : 1
},
{
"_id" : 5,
"TrackId" : 10,
"UnitPrice" : 0.99,
"Quantity" : 1
},
{
"_id" : 6,
"TrackId" : 12,
"UnitPrice" : 0.99,
"Quantity" : 1
}
]
}
]
}
为了解决这个问题并实现返回总销售额的目标,我创建了这个新查询
db.Employee.aggregate([{$unwind: "$_id"}, {$lookup: {from: "Invoice", localField: "_id", foreignField: "_id", as: "Invoices"}}, {$match: {_id: 2}}, {$group: {_id: "$_id", Total: {$sum: "$Total"}}}]).pretty()
虽然它只返回{“\u id”:2,“Total”:0}
在研究了其他问题后,我认为这可能是因为文档是嵌套的,尽管尝试了潜在的解决方案,但没有产生任何输出。没有好的错误,但什么也没有发生。以下是我尝试的查询:
db.Employee.aggregate([{$unwind: "$_id"}, {$unwind: "$_id.Invoices"}, {$unwind: "$_id.Invoices.InvoiceLines"}, {$lookup: {from: "Invoice", localField: "_id", foreignField: "_id", as: "Invoices"}}, {$match: {_id: 2}}, {$group: {_id: "$_id", Total: {$sum: "$Total"}}}]).pretty()
我不明白为什么这个查询没有返回总数。我尝试过的一切都失败了。感谢您的帮助
编辑:
我的数据库结构如下:员工>客户>发票。客户通过SupportRepId引用员工,该id与员工id相同,因为每个客户都被分配了一名员工,而发票包含客户id,因为每个发票都有一个客户。所以我想根据员工id获取所有发票和总额
员工示例:
{
"_id":3,
"LastName":"Peacock",
"FirstName":"Jane",
"Title":"Sales Support Agent",
"ReportsTo":2,
"BirthDate": ISODate("1973-08-29T00:00:00 Z"),
"HireDate": ISODate("2002-04-01T00:00:00 Z"),
"Address":"1111 6 Ave SW",
"City":"Calgary",
"State":"AB",
"Country":"Canada",
"PostalCode":"T2P 5M5",
"Phone":"+1 (403) 262-3443",
"Fax":"+1 (403) 262-6712",
"Email":"jane@chinookcorp.com"
}
客户示例:
{
"_id":1,
"FirstName":"Luís",
"LastName":"Gonçalves",
"Company":"Embraer - Empresa Brasileira de Aeronáutica S.A.",
"Address":"Av. Brigadeiro Faria Lima, 2170",
"City":"São José dos Campos",
"State":"SP",
"Country":"Brazil",
"PostalCode":"12227-000",
"Phone":"+55 (12) 3923-5555",
"Fax":"+55 (12) 3923-5566",
"Email":"luisg@embraer.com.br",
"SupportRepId":3
}
发票示例:
{
"_id":2,
"CustomerId":4,
"InvoiceDate": ISODate("2009-01-02T00:00:00 Z"),
"BillingAddress":"Ullevålsveien 14",
"BillingCity":"Oslo",
"BillingState":null,
"BillingCountry":"Norway",
"BillingPostalCode":"0171",
"Total":3.96,
"InvoiceLines":[
{
"_id":3,
"TrackId":6,
"UnitPrice":0.99,
"Quantity":1
},
{
"_id":4,
"TrackId":8,
"UnitPrice":0.99,
"Quantity":1
},
{
"_id":5,
"TrackId":10,
"UnitPrice":0.99,
"Quantity":1
},
{
"_id":6,
"TrackId":12,
"UnitPrice":0.99,
"Quantity":1
}
]
}
看看这是否有效
db.Employee.aggregate([
{
$match: {
"Employee._id": 2
}
},
{
$lookup: {
from: "Customer",
localField: "_id",
foreignField: "customer.SupportRepId",
as: "customer"
}
},
{
$lookup: {
from: "Invoice",
localField: "customer._id",
foreignField: "invoice.CustomerId",
as: "invoice"
}
}
])
这是因为
{$match:{{u id:2}}
它只匹配\u id
为2Hi的文档,匹配id用于将id为2的员工与该员工服务的所有客户进行匹配,但我的输出仅显示一个,而不是应该显示的5个。啊,我看到我正在将员工中的id 2与id为2的发票进行匹配,而不是所有id为2的发票。正确。从发票文件中提供更多样本也有助于澄清问题。您是否保存了这些发票所属销售人员的任何信息?正如您所说,您正在将发票id与销售人员id进行匹配。我添加了员工、客户和发票数据的示例,并简要说明了员工如何通过客户连接到发票。全部编辑后。输入查询时没有输出。我可能输入了错误的字段,请检查这些字段并重试。这也可能不是您要查找的答案。你可能需要做嵌套查找是的,它仍然不起作用,我对它做了一些修改,产生了一些混乱。它似乎返回所有客户,但没有发票。我将查看您建议的嵌套查找。看看这个问题。看起来和你的问题很相似