Mongo Db : elemMatch query on multiple array - mongodb

Please find below document structure of mongo Db
{ _id : 0,
name : "Employee1",
distributionList :[ { dlname : "ALLEmployee"}, {dlname:"financeall"} ],
csrActivity : [ {activityname : "blooddonation"}, {activityname : "tree plantation"} ]
}
I want list of employee belonging to financeall distribution list and opted to volunteer tree plantation CSR activity.
Expected resultset as below
{ _id : 0,
name : "Employee1",
distributionList :[{dlname:"financeall"} ],
csrActivity : [ {activityname : "tree plantation"} ]
}
But so far able to achieve below output from query
Query :
db.employee.find(
{name : "Employee1"},
{distributionList : {$eleMatch : {dlname : "financeall"}}}
)
Output :
{ _id : 0,
name : "Employee1",
distributionList :[{dlname:"financeall"} ]
}
Using $elemMatch to get the desired output but unable to find how to use it on multiple array within same document. Also tried certain combination but unable to get desired result.
Below query tried but not getting desired output
db.employee.find(
{name : "Employee1"},
{distributionList : {$eleMatch : {dlname : "financeall"}}},
{csrActivity: {$eleMatch : {activityname : "tree plantation"}}}
)
Any help will be highly appreciated

You only misspelled the projection operator $elemMatch
The correct query is:
db.employee.find(
{
name: "Employee1"
}, {
distributionList: {
$elemMatch: {
dlname: "financeall"
}
},
csrActivity: {
$elemMatch: {
activityname: "tree plantation"
}
}
}
)

Related

MongoDB get all embedded documents where condition is met

I did this in my mongodb:
db.teams.insert({name:"Alpha team",employees:[{name:"john"},{name:"david"}]});
db.teams.insert({name:"True team",employees:[{name:"oliver"},{name:"sam"}]});
db.teams.insert({name:"Blue team",employees:[{name:"jane"},{name:"raji"}]});
db.teams.find({"employees.name":/.*o.*/});
But what I got was:
{ "_id" : ObjectId("5ddf3ca83c182cc5354a15dd"), "name" : "Alpha team", "employees" : [ { "name" : "john" }, { "name" : "david" } ] }
{ "_id" : ObjectId("5ddf3ca93c182cc5354a15de"), "name" : "True team", "employees" : [ { "name" : "oliver" }, { "name" : "sam" } ] }
But what I really want is
[{"name":"john"},{"name":"oliver"}]
I'm having a hard time finding examples of this without using some kind of programmatic iterator/loop. Or examples I find return the parent document, which means I'd have to parse out the embedded array employees and do some kind of UNION statement?
Eg.
How to get embedded document in mongodb?
Retrieve only the queried element in an object array in MongoDB collection
Can someone point me in the right direction?
Please add projections to filter out the fields you don't need. Please refer the project link mongodb projections
Your find query should be constructed with the projection parameters like below:
db.teams.find({"employees.name":/.*o.*/}, {_id:0, "employees.name": 1});
This will return you:
[{"name":"john"},{"name":"oliver"}]
Can be solved with a simple aggregation pipeline.
db.teams.aggregate([
{$unwind : "$employees"},
{$match : {"employees.name":/.*o.*/}},
])
EDIT:
OP Wants to skip the parent fields. Modified query:
db.teams.aggregate([
{$unwind : "$employees"},
{$match : {"employees.name":/.*o.*/}},
{$project : {"name":"$employees.name",_id:0}}
])
Output:
{ "name" : "john" }
{ "name" : "oliver" }

MongoDB query on nested array

I have a MongoDB collection containing documents like this:
"_id" : "d0888171-473d-46c7-a9c2-e18dfa141998",
"NUMBER" : 111111,
"SECURITIES" : [
{
"FK_GROUPS_ID" : ObjectId("59d4e02540b8f85428c827f9"),
"ACCESS_LEVEL" : "r"
},
{
"FK_GROUPS_ID" : ObjectId("59d24bce184fcd62968a21a3"),
"ACCESS_LEVEL" : "rw"
}
]
}
How to find all documents with a specific FK_GROUPS_ID in SECURITIES array?
Thanks
db.collection.find({'SECURITIES.FK_GROUPS_ID' : ObjectId("GroupsIdString")});

Positional operator and field limitation

In a find query projection, fields I specify after the positional operator are ignored and the whole document is always returned.
'myArray.$.myField' : 1 behave exactly like 'myArray.$' : 1
the positional operator selects the right document. But this document is quite big. I would like to project only 1 field from it.
Exemple:
db.getCollection('match').find({"participantsData.id" : 0001}, { 'participantsData.$.id': 1, })
here the response I have
{
"_id" : "myid",
"matchCreation" : 1463916465614,
"participantsData" : [
{
"id" : 0001,
"plenty" : "of",
"other" : "fields",
"and" : "subdocuments..."
}
]
}
This is what I want
{
"_id" : "myid",
"matchCreation" : 1463916465614,
"participantsData" : [
{
"id" : 0001
}
]
}
Is it possible with mongo?
Yes it can be done in mongo
Please try the below query
db.getCollection('match').find(
{"participantsData.id" : 0001},
{"participantsData.id": 1, "matchCreation": 1 })
This will give you the below result
{
"_id" : "myid",
"matchCreation" : 1463916465614,
"participantsData" : [
{
"id" : 1
}
]
}

Mongo query to return distinct count, large documents

I need to be able to get a count of distinct 'transactions' the problem I'm having is that using .distinct() comes back with an error because the documents too large.
I'm not familiar with aggregation either.
I need to be able to group it by 'agencyID' as you see below there are 2 different agencyID's
I need to be able to count transactions where the agencyID is 01721487 etc
db.myCollection.distinct("bookings.transactions").length
this doesn't work as I need to be able to group by agencyID and if there are too many results I get an error saying it's too large.
{
"_id" : ObjectId("5624a610a6e6b53b158b4744"),
"agencyID" : "01721487",
"paxID" : "-530189664",
"bookings" : [
{
"bookingID" : "24232",
"transactions" : [
{
"tranID" : "001",
"invoices" : [
{
"invNum" : "1312",
"type" : "r",
"inv_date" : "20150723",
"inv_time" : "0953",
"inv_val" : -300
}
],
"tranType" : "Fee",
"tranDate" : "20150723",
"tranTime" : "0952",
"opCode" : "admin",
"udf_1" : "j s"
}
],
"acctID" : "acct11",
"agt_id" : "xy"
}
],
"title" : "",
"firstname" : "",
"surname" : "f bar"
}
I've also tried this but it didn't work for me.
thank you for text data -
this is something you could play with:
db.kieron.aggregate([{
$unwind : "$bookings"
}, {
$match : {
"bookings.transactions" : {
$exists : true,
$not : {
$size : 0
}
}
}
}, {
$group : {
_id : "$agencyID",
count : {
$sum : {
$size : "$bookings.transactions"
}
}
}
}
])
as there is nested array we need to unwind it first, and then we can check size of inner array.
Happy reporting!

get a mongo document based in two different values

I have the following document structure
{
"_id" : "aaa0001",
"path" : "/some/path",
"information" : {
"name" : "info"
},
"colors" : {
"colors" : [
{
"key" : "AAAA001",
"name" : "White"
},
{
"key" : "BBBB002",
"name" : "Black"
}
]
}
}
the idea is that I have to return the document by the color key. I have two parameters the "path" and the "color", so, I was trying to make something like this
db.components.find(
{$and:[
{"path" : "/some/path"},
{"colors":{"colors" : {$elemMatch: { "key" : "AAAA001" } } } }
]})
I'm getting the following message "Script is executed successfully, but there is no results to show".
Can anyone give me some directions regarding this?
thanks
Use the following query:
db.components.find({
"path": "/some/path",
"colors.colors.key" : "AAAA001"
})
MongoDB expects query document to contain field-value pairs { <field>: <value> }. So, in your example you're querying for a document with colors field equal to:
{"colors" : {$elemMatch: { "key" : "AAAA001" } } }
As for $and and $elemMatch operators, you don't need them in such a simple query.
For more information read Query Documents.
Update
You can also select only matching subdocument from colors array using Positional Operator $:
db.components.find({
"path": "/some/path",
"colors.colors.key" : "AAAA001"
}, {
_id: 0,
"colors.colors.$": 1
})
Though, you won't be able to change your documents structure, thus getting
{ "colors" : { "colors" : [ { "key" : "AAAA001", "name" : "White" } ] } }