Develop Reference

How do I return full documents containing a distinct value using Spring Framework Aggregation?

Say I have some documents like this:
{
"name" : "Wendy",
"phone" : "123",
"GroupId" : 1
},
{
"name" : "Tom",
"phone" : "234",
"GroupId" : 1
},
{
"name" : "Sally",
"phone" : "345",
"GroupId" : 3
},
{
"name" : "Bob",
"phone" : "456",
"GroupId" : 3
},
{
"name" : "Cortana",
"phone" : "567",
"GroupId" : 7
}
I'd like to return a list of full-data documents that contains the first occurrence of each distinct GroupId. I'm thinking Aggregation is the best route for a task like this. Here is what I have so far:
MatchOperation matchStage = Aggregation.match(new Criteria());
GroupOperation groupStage = Aggregation.group("GroupId").first("$$CURRENT").as("??");
// I know the above line is semi-nonsensical
Aggregation aggregation = Aggregation.newAggregation(matchStage, groupStage);
// I only need help creating the aggregation object, beyond this is just a MongoOperations aggregate call
It should be noted that I don't necessarily need to use aggregation so if there is a way to achieve this using a simple "find" then I'm okay with that.
I'm a MongoDb noob, sorry if my "have tried" section is not very useful. However, this is what I would want back:
{
"name" : "Wendy",
"phone" : "123",
"GroupId" : 1
},
{
"name" : "Sally",
"phone" : "345",
"GroupId" : 3
},
{
"name" : "Cortana",
"phone" : "567",
"GroupId" : 7
}

Try this. $first helps to get the first occurrence of the data
Aggregation aggregation = Aggregation.newAggregation(
group("GroupId")
.first("name").as("name")
.first("GroupId").as("GroupId")
.first("phone").as("pnone"),
project().andExclude("_id")
).withOptions(AggregationOptions.builder().allowDiskUse(Boolean.TRUE).build());
return mongoTemplate.aggregate(aggregation, mongoTemplate.getCollectionName(YOUR_COLLECTION_NAME.class), Object.class).getMappedResults();
Working Mongo playground

Trouble translating a MongoDB update query into spring boot

In my mongo database, I have the following document:
{
"_id" : ObjectId("5d1a08d2329a3c1374f176df"),
"associateID" : "1234567",
"associatePreferences" : [
{
"type" : "NOTIFICATION",
"serviceCode" : "service-code",
"eventCode" : "test-template",
"preferences" : [
"TEXT",
"EMAIL"
]
},
{
"type" : "URGENT_NOTIFICATION",
"serviceCode" : "service-code",
"eventCode" : "test-template",
"preferences" : [
"TEXT"
]
}
]
}
I am trying to add new elements to the preferences arrays based off of a given type, serviceCode, and eventCode. I was able to write this query in mongo as shown below:
db.user_communication_preferences.update(
{'associateID':'testassociate'},
{$addToSet:{'associatePreferences.$[element].preferences':"UPDATE"}},
{arrayFilters:[
{'element.serviceCode':'service-code',
'element.eventCode':'test-template',
'element.type':'NOTIFICATION'
}
]}
)
I am trying to translate this query into a java spring boot application. I saw some posts on here about doing this, but I didn't see any that incorporated arrayFilters. Can anyone lead me down the right path?

Query to find a subdocument in MongoDB

Alright, i've got a simple question. I have a simple Document in MongoDB which holds a sub-document called "penalties".
Now i want to find the Document (here with the _id "Cammeritz") by a String in the sub-document ("penalties"), e.g. "penaltyid = 0f77d885-6597-3f47-afb1-0cee2ea3ece1". Can you maybe help me? Best would be an explanation for Java but it is okay if you maybe just help with a normal MongoDB query.
{
"_id" : "Cammeritz",
"penalties" : [
{
"_id" : null,
"date" : ISODate("2017-09-25T20:01:23.582Z"),
"penaltyid" : "0f77d885-6597-3f47-afb1-0cee2ea3ece1",
"reason" : "Hacking",
"teammember" : "Luis",
"type" : "ban"
},
{
"_id" : null,
"date" : ISODate("2017-09-25T20:01:23.594Z"),
"penaltyid" : "7f5411b0-e66a-33b3-ac4f-4f3159aa88a9",
"reason" : "Spam",
"teammember" : "BluingFX",
"type" : "kick"
}
],
"isBanned" : true,
"isMuted" : false
}

Oops, I misread your question. You'll need to use dot notation. db.collection.find( { penalties.penaltyid: '0f77d885-6597-3f47-afb1-0cee2ea3ece1' } ) For more info see Query on a Nested Field.
Original answer:
db.collection.find( { penalties: "0f77d885-6597-3f47-afb1-0cee2ea3ece1" } ) should work. For more see Query an Array for an Element from the mongodb docs. I'm not very familiar with Java so I can't help much there.

Mongo query inside Hashmap with unknown hash key

Platform: MongoDB, Spring, SpringDataMongoDB
I have a collection called "Encounter" with below structure
Encounter:
{ "_id" : "49a0515b-e020-4e0d-aa6c-6f96bb867288",
"_class" : "com.keype.hawk.health.emr.api.transaction.model.Encounter",
"encounterTypeId" : "c4f657f0-015d-4b02-a216-f3beba2c64be",
"visitId" : "8b4c48c6-d969-4926-8b8f-05d2f58491ae",
"status" : "ACTIVE",
"form" :
{
"_id" : "be3cddc5-4cec-4ce5-8592-72f1d7a0f093",
"formCode" : "CBC",
"fields" : {
"dc" : {
"label" : "DC",
"name" : "tc",
},
"tc" : {
"label" : "TC",
"name" : "tc",
},
"notes" : {
"label" : "Notes",
"name" : "notes",
}
},
"notes" : "Blood Test",
"dateCreated" : NumberLong("1376916746564"),
"dateModified" : NumberLong("1376916746564"),
"staffCreated" : 10013,
"staffModified" : 10013
},
}
The element "fields" is represented using a Java Hashmap as:
protected LinkedHashMap<String, Field> fields;
The Key to the hashmap () is not fixed, but generated at run time.
How do I query to get all documents in the collection where "label" = "TC"?
It's not possible to query like db.encounter.find({'form.fields.dc.label':'TC'}) because the element name 'dc' is NOT known. I want to skip that postion and the execute query, something like:
db.encounter.find({'form.fields.*.label':'TC'});
Any ideas?
Also, how do I best use indexes in this scenario?

If fields were an array and your key a part of the sub-document instead:
"fields" : [
{ "key" : "dc",
"label" : "DC",
"name" : "dc"
},
{ "key" : "tc",
"label" : "TC",
"name" : "tc"
}
]
In this case, you could simply query for any sub-element inside the array:
db.coll.find({"form.fields.label":"TC"})
Not sure how you would integrate that with Spring, but perhaps the idea helps? As far as indexes are concerned, you can index into the array, which gives you a multi-key index. Basically, the index will have a separate entry pointing to the document for each array value.

ElasticSearch : Sorting by nested documents' values

I am facing a trouble in the use of ElasticSearch for my java application.
I explain myself, I have a mapping, which is something like :
{
"products": {
"properties": {
"id": {
"type": "long",
"ignore_malformed": false
},
"locations": {
"properties": {
"category": {
"type": "long",
"ignore_malformed": false
},
"subCategory": {
"type": "long",
"ignore_malformed": false
},
"order": {
"type": "long",
"ignore_malformed": false
}
}
},
...
So, as you can see, I receive a list of products, which are composed of locations. In my model, this locations are all the categories' product. It means that a product can be in 1 or more categories. In each of this category, the product has an order, which is the order the client wants to show them.
For instance, a diamond product can have a first place in Jewelry, but the third place in Woman (my examples are not so logic ^^).
So, when I click on Jewelry, I want to show this products, ordered by the field locations.order in this specific category.
For the moment, when I search all the products on a specific category the response for ElasticSearch that I receive is something like :
{"id":5331880,"locations":[{"category":5322606,"order":1},
{"category":5883712,"subCategory":null,"order":3},
{"category":5322605,"subCategory":6032961,"order":2},.......
Is it possible to sort this products, by the element locations.order for the specific category I am searching for ? For instance, if I am querying the category 5322606, I want the order 1 for this product to be taken.
Thank you very much beforehand !
Regards,
Olivier.

First a correction of terminology: in Elasticsearch, "parent/child" refers to completely separate docs, where the child doc points to the parent doc. Parent and children are stored on the same shard, but they can be updated independently.
With your example above, what you are trying to achieve can be done with nested docs.
Currently, your locations field is of type:"object". This means that the values in each location get flattened to look something like this:
{
"locations.category": [5322606, 5883712, 5322605],
"locations.subCategory": [6032961],
"locations.order": [1, 3, 2]
}
In other words, the "sub" fields get flattened into multi-value fields, which is of no use to you, because there is no correlation between category: 5322606 and order: 1.
However, if you change locations to be type:"nested" then internally it will index each location as a separate doc, meaning that each location can be queried independently, using the dedicated nested query and filter.
By default, the nested query will return a _score based upon how well each location matches, but in your case you want to return the highest value of the order field from any matching children. To do this, you'll need to use a custom_score query.
So let's start by creating the index with the appropriate mapping:
curl -XPUT 'http://127.0.0.1:9200/test/?pretty=1' -d '
{
"mappings" : {
"products" : {
"properties" : {
"locations" : {
"type" : "nested",
"properties" : {
"order" : {
"type" : "long"
},
"subCategory" : {
"type" : "long"
},
"category" : {
"type" : "long"
}
}
},
"id" : {
"type" : "long"
}
}
}
}
}
'
The we index your example doc:
curl -XPOST 'http://127.0.0.1:9200/test/products?pretty=1' -d '
{
"locations" : [
{
"order" : 1,
"category" : 5322606
},
{
"order" : 3,
"subCategory" : null,
"category" : 5883712
},
{
"order" : 2,
"subCategory" : 6032961,
"category" : 5322605
}
],
"id" : 5331880
}
'
And now we can search for it using the queries we discussed above:
curl -XGET 'http://127.0.0.1:9200/test/products/_search?pretty=1' -d '
{
"query" : {
"nested" : {
"query" : {
"custom_score" : {
"script" : "doc[\u0027locations.order\u0027].value",
"query" : {
"constant_score" : {
"filter" : {
"and" : [
{
"term" : {
"category" : 5322605
}
},
{
"term" : {
"subCategory" : 6032961
}
}
]
}
}
}
}
},
"score_mode" : "max",
"path" : "locations"
}
}
}
'
Note: the single quotes within the script have been escaped as \u0027 to get around shell quoting. The script actually looks like this: "doc['locations.order'].value"
If you look at the _score from the results, you can see that it has used the order value from the matching location:
{
"hits" : {
"hits" : [
{
"_source" : {
"locations" : [
{
"order" : 1,
"category" : 5322606
},
{
"order" : 3,
"subCategory" : null,
"category" : 5883712
},
{
"order" : 2,
"subCategory" : 6032961,
"category" : 5322605
}
],
"id" : 5331880
},
"_score" : 2,
"_index" : "test",
"_id" : "cXTFUHlGTKi0hKAgUJFcBw",
"_type" : "products"
}
],
"max_score" : 2,
"total" : 1
},
"timed_out" : false,
"_shards" : {
"failed" : 0,
"successful" : 5,
"total" : 5
},
"took" : 9
}

Just add a more updated version related to sorting parent by child field.
We can query parent doc type sorted by child field ('count' e.g.) similar as follows.
https://gist.github.com/robinloxley1/7ea7c4f37a3413b1ca16