已编辑的问题：我有一个汇总脚本，该脚本尝试经历以下阶段。我遇到的问题是注释部分。
我遇到的问题是下面管道中的3号和6号。我在脚本下方包含一个示例原始文档。
对于数字3，如果我取消注释该部分，它将运行，但仅返回一个文档，并且某些字段消失。当我将其注释掉时，可以根据需要获取正确数量的文档。
对于数字6，我认为当前计数是针对订单项而不是订单项来自的文档。我想按组最多一个级别来计算文档，但不确定如何。
谢谢，马特
01在日期范围内查找某种类型的文档
02对按创建日期排序的文档进行排序以标识重复项
03使用$ first
从所有文档的最新版本中选择值04 $ unwind line_items并仅对类别的line_items应用$ match
05为YYYYMM创建一个值以按（日期作为数字）左6个位置分组
06按组计数文档（我认为这仅提供line_items的数量，而不是文档的数量）
07预期格式的项目值带有附加标签（$ literal值）
db.getCollection("9SP_Data").aggregate([
// find documents of a type and within a number range
{"$match" : {"_id.object_category" : "revenue-transaction"
,"_id.transaction_date": {
$gte: 20160101000000,
$lt: 20170101000000
},
}},
// sort into order so that if duplicates, the new document listed at top
{$sort : { "_id.connection":1,
"_id.company":1,
"_id.transaction_reference":1,
"object_creation_date": -1 }},
/*
// THIS IS MY PROBLEM AREA - I don't have all the fields and it results in 1 document created
{$group : { _id: {"$transaction_reference",
"company" : {$first: "$_id.connection"},
"transaction_date" : {$first: "$_id.transaction_date"},
"object_category" : {$first: "$_id.object_category"},
"transaction_status" : {$first: "$_id.transaction_status"},
"object_origin_category" : {$first: "$_id.object_origin_category"},
"object_origin_sub_category" : {$first: "$_id.object_origin_sub_category"},
"object_origin" : {$first: "$_id.object_origin"},
"line_items" : {$first: "$line_items"}}},
*/
{"$unwind" : "$line_items"},
{"$match" : {"line_items.item_category":"sales-revenue"}},
{"$group" : {
"_id":
{
"company" : "$_id.connection",
"sum_by_date": {$trunc:{$divide: ["$_id.transaction_date", 100000000 ]}},
// 10000000000 - by year
// 100000000 - by month
// 1000000 - by date
// 10000 - by hour
// 100 - by minute
"category" : "$line_items.item_category",
"origin_category" : "$_id.object_origin_category",
"object_origin_type" : "$_id.object_origin_type",
"object_origin" : "$_id.object_origin"
},
"metric_value" : { $sum: "$line_items.item_net_total_value" },
// count number of documents (I think this is counting line_items but I need number of distinct documents by _id.transaction_reference)
"metric_volume":{$sum:1}}
},
// format the output to include the following values
{$project : {
"_id.company" : "$_id.company",
"_id.metric_name" : {$literal : "revenue"},
"_id.metric_category" : {$literal : "sales"},
"_id.metric_type" : {$literal : "month"},
"_id.metric_lookup" : "$_id.sum_by_date",
"_id.object_origin_category": "$_id.origin_category",
"_id.object_origin_type" : "$_id.object_origin_type",
"_id.object_origin" : "$_id.object_origin",
"metric_value" : "$metric_value",
"metric_volume" : "$metric_volume"
}}
])
集合中的示例文档：
{
"_id" : {
"connection" : "cb1c4a56-1544-4e9d-a433-abb33429a300",
"transaction_date" : 20171129170558,
"transaction_date_utc" : "2017-11-29 17:05:58",
"object_class" : "goods-service-transaction",
"object_category" : "revenue-transaction",
"object_type" : "receipt",
"object_origin_category" : "point-of-sale",
"object_origin_type" : "offline",
"object_origin" : "vend",
"transaction_status" : "CLOSED",
"related_reference" : "85"
},
"object_creation_date" : "20181210120904",
"party_identifier" : "WALKIN",
"staff_identifier" : "02dcd191-ae2b-11e6-f485-7967ed9c6343",
"staff_name" : "uat1@9spokes.com",
"line_items" : [
{
"item_name" : "Summer Dress / 10",
"item_system_id" : "02dcd191-ae20-11e6-f485-7967ee5a21ee",
"item_identifier" : "10017",
"item_category" : "sales-revenue",
"item_type" : "goods-service",
"item_quantity" : 1,
"item_net_unit_sale_value" : 102.2727,
"item_net_unit_discount_value" : 0,
"item_unit_tax_value" : 11.3636,
"item_net_total_value" : 102.2727,
"item_total_tax_value" : 11.36364,
"item_total_gross_value" : 113.63636
},
{
"item_name" : "Dress Shirt / Polyester / Medium",
"item_system_id" : "02dcd191-ae20-11e6-f485-7967eee35001",
"item_identifier" : "10023",
"item_category" : "sales-revenue",
"item_type" : "goods-service",
"item_quantity" : 1,
"item_net_unit_sale_value" : 61.3636,
"item_net_unit_discount_value" : 0,
"item_unit_tax_value" : 6.8182,
"item_net_total_value" : 61.3636,
"item_total_tax_value" : 6.81818,
"item_total_gross_value" : 68.18182
}
]
}