我有什么:
list of company names : [bmw, tata, ferrari,...]
transmission: Manual or Automatic3.
car color: Red or White etc
model year: 2010 to 2014
Min Price & Max Price. --> Price range
我现在能做什么:如果我只有一个对象(即公司中的一个公司)，那么我会做类似的事情:
query = {{transmission_type : transmission}, {color : car_color}, {year : model_year}, { $range: [ 0, "$PriceInINR", 25 ] } }
db.companies.cars.find(query)
但是这里首先有很多公司，然后每个公司都有一个汽车列表。
我怎样才能进行这样的查询？
- 我想要一个考虑价格范围的查询。
- 另一个没有价格范围条件。
早期想法:我认为我可以单独查询每个公司，因为我知道公司名称。因此单独查找结果然后将它们推送到数组中。
我应该怎么做，还有其他建议吗？
Mongo DB 中公司集合的实际结构
{
"_id" : ObjectId("5b8ef8b78cc390cca71aa0e5"),
"company_location" : "USA",
"company_name" : "buick",
"__v" : 0,
"cars" : [
{
"_id" : ObjectId("5b8ef8b6d1a7c2156417de56"),
"model" : "ENCLAVE",
"year" : 2014,
"PriceInINR" : 2537993,
"trim" : "Leather FWD",
"engine" : "SPORT UTILITY 4-DR",
"body" : "3.6L V6 DOHC 24V",
"color" : "Silver",
"transmission_type" : "Manual",
"dealer_id" : "5b8ee03ffe42df0d94de785d"
},
{
"_id" : ObjectId("5b8ef8b6d1a7c2156417de5d"),
"model" : "LaCrosse",
"year" : 2011,
"PriceInINR" : 4677427,
"trim" : "CXL FWD",
"engine" : "SEDAN 4-DR",
"body" : "3.6L V6 DOHC 24V",
"color" : "Grey",
"transmission_type" : "Automatic",
"dealer_id" : "5b8ee03ffe42df0d94de785d"
},
{
"_id" : ObjectId("5b8ef8b7d1a7c2156417de8e"),
"model" : "ENCORE",
"year" : 2013,
"PriceInINR" : 4808616,
"trim" : "Leather FWD",
"engine" : "SPORT UTILITY 4-DR",
"body" : "1.4L L4 DOHC 16V TURBO",
"color" : "Yellow",
"transmission_type" : "Manual",
"dealer_id" : "5b8ee03ffe42df0d94de785d"
},
{
"_id" : ObjectId("5b8ef8b7d1a7c2156417dece"),
"model" : "LaCrosse",
"year" : 2011,
"PriceInINR" : 868875,
"trim" : "CXL FWD",
"engine" : "SEDAN 4-DR",
"body" : "2.4L L4 DOHC 16V",
"color" : "Grey",
"transmission_type" : "Automatic",
"dealer_id" : "5b8ee03ffe42df0d94de785d"
},
{
"_id" : ObjectId("5b8ef9c1f0412315aa07b65a"),
"model" : "VERANO",
"year" : 2013,
"PriceInINR" : 4380113,
"trim" : "Base",
"engine" : "SEDAN 4-DR",
"body" : "2.4L L4 DOHC 16V FFV",
"color" : "Metallic White",
"transmission_type" : "Automatic",
"dealer_id" : "5b8ee03ffe42df0d94de785d"
}
]}
{
"_id" : ObjectId("5b8ef8b78cc390cca71aa0e7"),
"company_location" : "USA",
"company_name" : "gmc",
"__v" : 0,
"cars" : [
{
"_id" : ObjectId("5b8ef8b6d1a7c2156417de57"),
"model" : "TERRAIN",
"year" : 2013,
"PriceInINR" : 3851710,
"trim" : "SLE2 FWD",
"engine" : "SPORT UTILITY 4-DR",
"body" : "2.4L L4 DOHC 16V FFV",
"color" : "Yellow",
"transmission_type" : "Manual",
"dealer_id" : "5b8ee03ffe42df0d94de785d"
},
{
"_id" : ObjectId("5b8ef8b6d1a7c2156417de5b"),
"model" : "YUKON",
"year" : 2015,
"PriceInINR" : 3129397,
"trim" : "SLE 2WD",
"engine" : "SPORT UTILITY 4-DR",
"body" : "5.3L V8 OHV 16V",
"color" : "Silver",
"transmission_type" : "Manual",
"dealer_id" : "5b8ee03ffe42df0d94de785d"
},
{
"_id" : ObjectId("5b8ef9c1f0412315aa07b659"),
"model" : "SIERRA 1500",
"year" : 2014,
"PriceInINR" : 3649025,
"trim" : "SLE Crew Cab 2WD",
"engine" : "CREW CAB PICKUP 4-DR",
"body" : "5.3L V8 OHV 16V",
"color" : "Metallic White",
"transmission_type" : "Automatic",
"dealer_id" : "5b8ee03ffe42df0d94de785d"
},
{
"_id" : ObjectId("5b8ef9c1f0412315aa07b666"),
"model" : "TERRAIN",
"year" : 2012,
"PriceInINR" : 1896832,
"trim" : "SLT1 FWD",
"engine" : "SPORT UTILITY 4-DR",
"body" : "3.0L V6 DOHC 24V",
"color" : "Metallic White",
"transmission_type" : "Automatic",
"dealer_id" : "5b8ee03ffe42df0d94de785d"
},
{
"_id" : ObjectId("5b8ef9c1f0412315aa07b650"),
"model" : "ACADIA",
"year" : 2012,
"PriceInINR" : 2541355,
"trim" : "Denali AWD",
"engine" : "SPORT UTILITY 4-DR",
"body" : "3.6L V6 DOHC 24V",
"color" : "Metallic White",
"transmission_type" : "Automatic",
"dealer_id" : "5b8ee03ffe42df0d94de785d"
}
]
}
最佳答案
您可以使用聚合。 $unwind将为每辆车输出一个文档。然后$match在您的示例中用于代替 find()。
const transmission = 'Manual'
const car_color = 'Yellow'
const model_year = 2013
const min_price = 3500000
const max_price = 4000000
const query = {
'cars.transmission_type': transmission,
'cars.color': car_color,
'cars.year': model_year,
'cars.PriceInINR': { '$gte': min_price, '$lte': max_price }
}
db.companies.aggregate([
{ '$unwind': '$cars' },
{ '$match': query }
])
关于node.js - mongodb : find() query in a collection，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/52243910/