mongodb $in, search deeply nested subdocument - mongodb

Question

I have the following collections in mongo:
> db.styles.find({ "_id" : "EP01L"}).pretty();
{
"_id" : "EP01L",
"__v" : 5,
"categoryIds" : [
ObjectId("5550dcc7a14c976741483c89"),
ObjectId("5550dcc7a14c976741483c8d")
],
"collectionId" : ObjectId("5550dab4a14c9766418ff2af"),
"colours" : {
"WH" : [
{
"on_sale" : false,
"size_code_id" : "S",
"sku" : "EP01L-WH1"
},
],
"BL" : [
{
"on_sale" : false,
"size_code_id" : "S",
"sku" : "EP01L-BL1"
},
]
},
"fabric" : {
"material" : [
{
"_id" : ObjectId("5550dab4a14c9766418ff2c4"),
"value" : 100
}
],
"type" : ObjectId("5550dab4a14c9766418ff2d1"),
"weight" : {
"ounce" : {
"min" : 4
},
"gram" : {
"min" : 155
}
}
},
"name" : {
"es-ES" : "CAMISETA MANGA LARGA HOMBRE",
"it-IT" : "T-SHIRT UOMO MANICA LUNGA",
"en-UK" : "MEN’S LONG SLEEVE T-SHIRT",
"fr-FR" : "T-SHIRT HOMME MANCHES LONGUES"
},
}
and
> db.attributes.find({"name.en-UK": "Fabric"}).pretty();
{
"_id" : ObjectId("5550dab4a14c9766418ff2dc"),
"values" : {
"source" : [
{
"code" : 1,
"_id" : ObjectId("5550dab4a14c9766418ff2bf"),
"name" : {
"fr-FR" : "Coton",
"it-IT" : "Cotone",
"en-UK" : "Cotton",
"es-ES" : "Algodón"
}
},
{
"code" : 2,
"_id" : ObjectId("5550dab4a14c9766418ff2c0"),
"name" : {
"fr-FR" : "Viscose",
"it-IT" : "Viscosa",
"en-UK" : "Viscose",
"es-ES" : "Viscosa"
}
},
],
"name" : [
{
"_id" : ObjectId("5550dab4a14c9766418ff2cd"),
"name" : {
"en-UK" : "3-ply Loopback"
}
},
{
"_id" : ObjectId("5550dab4a14c9766418ff2db"),
"name" : {
"en-UK" : "Woven Twill"
}
}
]
},
"name" : {
"en-UK" : "Fabric"
}
}
I am trying to write a query to find all the style documents that where fabric.source is either Cotton or Viscose and fabric.name is Woven Twill.
this query gives me all the documents that have fabric.type are Cotton or Viscose
> db.styles.find( { "fabric.type": { $in: [ ObjectId("5550dab4a14c9766418ff2cd"), ObjectId("5550dab4a14c9766418ff2db") ] } } ).count();
3
>
but how do I find all the styles where the size_code_id is S and colours is WH?

Answer 1

Please check the below query :
db.styles.find({
$and:[
{ "colours.WH" :{ $exists:1 } } ,
{ "colours.WH.size_code_id" : "S"}
]
}
).pretty();
If you need to find for "WH" and "BL", you can query like below :
db.styles.find({
$or:[
{
$and:[
{ "colours.WH" :{ $exists:1 } } ,
{ "colours.WH.size_code_id" : "S"}
]
},
{
$and:[
{ "colours.BL" :{ $exists:1 } } ,
{ "colours.BL.size_code_id" : "S"}
]
}
]
}
).pretty();
P.S : If you need to query for the multiple colors say for some 5- 10 different colours, Then you should construct the query dynamically for all those colors using JavaScript language constructs.
Below is the TESTED code for constructing the query dynamically :
// Colours you want to search
var varray = new Array("WH","BL");
var fname = "colours", lname = "size_code_id";
var arr = new Array();
var mquery = {"$or":[]};
for( var i = 0; i < varray.length; i++ )
{
var query = { "$and" : []};
// This line will dynamically construct a key as "colours.WH"
var s1 = fname.concat(".").concat(varray[i]);
// This line will dynamically construct a key as "colours.WH.size_code_id"
var s2 = fname.concat(".").concat(varray[i]).concat(".").concat(lname);
var sub1 = {}, sub2 = {};
sub1[s1] = { $exists:1 };
sub2[s2] = "S";
query["$and"].push(sub1);
query["$and"].push(sub2);
arr.push(query);
}
mquery["$or"] =arr;
db.styles.find(mquery);