I am trying to figure out specific mongoDb query, so far unsuccessfully.
Documents in my collections looks someting like this (contain more attributes, which are irrelevant for this query):
[{
"_id": ObjectId("596e01b6f4f7cf137cb3d096"),
"code": "A",
"name": "name1",
"sys": {
"cts": ISODate("2017-07-18T12:40:22.772Z"),
}
},
{
"_id": ObjectId("596e01b6f4f7cf137cb3d097"),
"code": "A",
"name": "name2",
"sys": {
"cts": ISODate("2017-07-19T12:40:22.772Z"),
}
},
{
"_id": ObjectId("596e01b6f4f7cf137cb3d098"),
"code": "B",
"name": "name3",
"sys": {
"cts": ISODate("2017-07-16T12:40:22.772Z"),
}
},
{
"_id": ObjectId("596e01b6f4f7cf137cb3d099"),
"code": "B",
"name": "name3",
"sys": {
"cts": ISODate("2017-07-10T12:40:22.772Z"),
}
}]
What I need is to get current versions of documents, filtered by code or name, or both. Current version means that from two(or more) documents with same code, I want pick the one which has latest sys.cts date value.
So, result of this query executed with filter name="name3" would be the 3rd document from previous list. Result of query without any filter would be 2nd and 3rd document.
I have an idea how to construct this query with changed data model but I was hoping someone could lead me right way without doing so.
Thank you
Related
Not sure I am using the right terminology here, but assume following oversimplified JSON structure available in Mongo :
{
"_id": 1234,
"labels": {
"label1": {
"id": "l1",
"value": "abc"
},
"label3": {
"id": "l2",
"value": "def"
},
"label5": {
"id": "l3",
"value": "ghi"
},
"label9": {
"id": "l4",
"value": "xyz"
}
}
}
{
"_id": 5678,
"labels": {
"label1": {
"id": "l1",
"value": "hjk"
},
"label5": {
"id": "l5",
"value": "def"
},
"label10": {
"id": "l10",
"value": "ghi"
},
"label24": {
"id": "l24",
"value": "xyz"
}
}
}
I know my base element name (labels in the example), but I do not know the various sub elements I can have (so in this case the labelx names).
How can I group / count the existing elements (like as if I would be using a wildcard) so I would get some distinct overview like
"label1":2
"label3":1
"label5":2
"label9":1
"label10":1
"label24":1
as a result? So far I only found examples where you actually need to know the element names. But I don't know them and want to find some way to get all possible sub element names for a given top element for easy review.
In reality the label names can be pretty wild, I used labelx for readability in the example.
You can try below aggregation in 3.4.
Use $objectToArray to transform object to array of key value pairs followed by $unwind and $group on key to count occurrences.
db.col.aggregate([
{"$project":{"labels":{"$objectToArray":"$labels"}}},
{"$unwind":"$labels"},
{"$group":{"_id":"$labels.k","count":{"$sum":1}}}
])
I am working on mongodb Aggregation query but i don't know how to get the array value from the JSON by joining two collection, please go through my below sample JSON.
COKE Collection
[{
"name": "Mirinda",
"_id": "894567894769476948"
}, {
"name": "COKE",
"_id": "857856856879694769"
}, {
"name": "PEPSI",
"_id": "785485686846684684"
}]
COKE Order Collection
{
"_id": "0908080808031338013101",
"drink": [{
"name": "Mirinda",
"_id": "894567894769476948"
}, {
"name": "COKE",
"_id": "857856856879694769"
}, {
"name": "PEPSI",
"_id": "785485686846684684"
}]
}
Expected OutPut:
Miranda name and _id should come of Orders collection by passing _id.
Above sample son i want to get the name value by joining the collections _id, please kindly go through my post and let me know if you have any suggestion.
I have the following structure in MongoDB and I try to remove the documents that contains specific tags. I can't seem to be able to get the $pull work.
In this example, I would like to pull the nested doc that has has tags :["BB"]
Any help will be appreciated !
{
"_id": 123,
"socialItems": {
"facebook": [{
"name": "firstFacebook",
"id": 2
}, {
"name": "secondFB",
"id": 43
}],
"instagram": [{
"name": "firstNstagram",
"id": 4
}],
"pc": [{
"name": "firstPC",
"id": 55,
"tags": [
"ab"
]
}, {
"name": "secondPC",
"id": 66,
"tags": [
"BB"
]
}]
}
}
I assume you are trying to drop the nested 'pc' doc, from the array? You also don't mention if you're using a specific driver for this, so I've assumed you're running this in the Mongo shell.
The following will remove documents from the 'pc' property, when containing the 'BB' tag.
db.collectionName.update({'socialItems.pc.tags': 'BB'}, {$pull: {'socialItems.pc': {tags: 'BB'}}})
I have a collection with documents like this
"_id": ObjectId('55f02a779e6efb8'),
"msgId": "5fdf509c-5229-4e7c-87ff",
"statuses": [
{
"state": "QUEUED",
"timestamp": ISODate('2013-10-08T13:13:38.000Z')
},
{
"state": "PENDING",
"timestamp": ISODate('2013-10-08T13:13:49.000Z')
},
{
"state": "DELIVERED",
"timestamp": ISODate('2013-10-08T13:13:57.000Z')
}
]
I want to use project for assigning the last 2 (embedded docs) values of the nested array (the array size is not static) so as to use them in a group operation in later step.
I want sth like $slice(aggregation) but it is still not supported in the version of MongoDB I use (3.0.6).
Is there any way to access the 2 last elements of the array by their index and if not is there any other solution?
Say I have a document that looks something like this:
{
"_id": ObjectId("50b6a7416cb035b629000001"),
"businesses": [{
"name": "Biz1",
"id": ObjectId("50b6bc953e47dc923e000001")
}, {
"name": "Biz2",
"id": ObjectId("50b6ccebae0513bf52000001")
}, {
"name": "Biz3",
"id": ObjectId("50b6d015c58b414156000001")
}, {
"name": "Biz4",
"id": ObjectId("50b6d0c8a4cdd5e356000001")
}]
}
I want to remove
{
"name": "Biz3",
"id": ObjectId("50b6d015c58b414156000001")
}
from the array of businesses. I tried this (using business name instead of id for clarity):
db.users.update({'businesses.name':'Biz3'},{$pull:{'businesses.name':'Biz3'}})
but of course it didn't work. I know that the query part is correct because I get the document back when I do this:
db.users.find({'businesses.name' : 'Biz3'})
So the problem is with the update part.
Just ran a quick lil test and this works
I think trying db.users.update({'businesses.name':'Biz3'},{$pull:{'businesses':{'name':'Biz3'}}}) should do it