If I have a Documents defined as
[
{
"title": "title",
"tags": [ "cool", "amazing", "funny" ]
},
{
"title": "another title",
"tags": [ "nice", "amazing", "funny" ]
}
]
I'd like to be able to query with MongoTemplate in order to pass a list of values like ["cool","amazing"] and have in return the first collection above, not the second.
For what I mean to achieve, the $in condition doesn't seems enough.
I tried with the $all condition and from the Mongo console it works as I need, but in my code something isn't working and it takes forever for my query to elaborate. With the $in operator my code goes fast, instead.
My method in my repository (for other reasons, I have to do an aggregation as below):
public Page<MyDocument> findByProperties(String title, List<ObjectId> tags, Pageable page) {
final List<Criteria> criteria = new ArrayList<>();
Aggregation aggregation = null;
if (title != null && !title.isEmpty()) {
criteria.add(Criteria.where("title").is(title));
}
if (tags != null && !tags.isEmpty()) {
criteria.add(Criteria.where("MyBook.tags").all(tags));
}
if (!criteria.isEmpty()) {
aggregation = Aggregation.newAggregation(
Aggregation.lookup("from_collection", "_id", "idParent", "MyBook"),
Aggregation.unwind("MyBook"),
Aggregation.match(new Criteria().andOperator(criteria.toArray(new Criteria[0]))),
Aggregation.skip(page.getOffset()),
Aggregation.limit(page.getPageSize()),
Aggregation.sort(page.getSort())
);
} else {
aggregation = Aggregation.newAggregation(
Aggregation.lookup("from_collection", "_id", "idParent", "MyBook"),
Aggregation.unwind("MyBook"),
Aggregation.skip(page.getOffset()),
Aggregation.limit(page.getPageSize()),
Aggregation.sort(page.getSort())
);
}
List<MyDocument> results = mongoTemplate.aggregate(aggregation, "my_document", MyDocument.class).getMappedResults();
return PageableExecutionUtils.getPage(results, page,
() -> (long)results.size());
}
Looking at this answer, I tried with
criteria.add(Criteria.where("MyBook.tags").in(tags).all(tags));
But nothing changed, the query takes forever and not with the expected output.
Any ideas please? Thank you!
To find if tags array field contains all the members of youe array, your can use the bellow, if you need it to be in aggregation pipeline use the second.
In your query you have more stages, and more code, if you want to ask more if you can give example data and expected output in JSON, and what you want to do, so people can help.
Query1
find using $all operator
Test code here
db.collection.find({"tags": {"$all": ["cool","amazing"]}})
Query2
aggregation solution with set difference
Test code here
aggregate(
[{"$match":
{"$expr":
{"$eq": [{"$setDifference": [["cool", "amazing"], "$tags"]}, []]}}}])
Related
I am in the process of attempting to create a method that will compose a query using Spring Data and I have a couple of questions. I am trying to perform a query using top level attributes of a document (i.e. the id field) as well as attributes of an subarray.
To do so I am using a query similar to this:
db.getCollection("journeys").find({ "_id._id": "0104", "journeyDates": { $elemMatch: { "period": { $in: [ 1,2 ] } } } })
As you can see I would also like to filter using $in for the values of the subarray. Running the above query though result in wrong results, as if the $elemMatch is ignored completely.
Running a similiar but slightly different query like this:
db.getCollection("journeys").find({ "_id._id": { $in: [ "0104" ] } }, { journeyDates: { $elemMatch: { period: { $in: [ 1, 2 ] } } } })
does seem to yield better results but it returns the only first found element matching the $in of the subarray filter.
Now my question is, how can I query using both top level attributes as well subarrays using $in. Preferably I would like to avoid aggregations. Secondly, how can I translate this native Mongo query to a Spring data Query object?
I have a collection with documents of the following structure:
{
"category": "movies",
"movies": [
{
"name": "HarryPotter",
"language": "english"
},
{
"name": "Fana",
"language": "hindi"
}
]
}
I want to query with movie name="fana" and the response sholud be
{
"category": "movies",
"movies": [
{
"name": "HarryPotter",
"language": "english"
}
]
}
How do I get the above using spring mongoTemplate?
You can try something like this.
Non-Aggregation based approach:
public MovieCollection getMoviesByName() {
BasicDBObject fields = new BasicDBObject("category", 1).append("movies", new BasicDBObject("$elemMatch", new BasicDBObject("name", "Fana").append("size", new BasicDBObject("$lt", 3))));
BasicQuery query = new BasicQuery(new BasicDBObject(), fields);
MovieCollection groupResults = mongoTemplate.findOne(query, MovieCollection.class);
return groupResults;
}
Aggregation based approach:
import static org.springframework.data.mongodb.core.aggregation.Aggregation.*;
import static org.springframework.data.mongodb.core.query.Criteria.where;
public List<BasicDBObject> getMoviesByName() {
Aggregation aggregation = newAggregation(unwind("movies"), match(where("movies.name").is("Fana").and("movies.size").lt(1)),
project(fields().and("category", "$category").and("movies", "$movies")));
AggregationResults<BasicDBObject> groupResults = mongoTemplate.aggregate(
aggregation, "movieCollection", BasicDBObject.class);
return groupResults.getMappedResults();
}
$unwind of mongodb aggregation can be used for this.
db.Collection.aggregate([{
{$unwind : 'movies'},
{$match :{'movies.name' : 'fana'}}
}])
You can try the above query to get required output.
Above approaches provides you a solution using aggregation and basic query. But if you dont want to use BasicObject below code will perfectly work:
Query query = new Query()
query.fields().elemMatch("movies", Criteria.where("name").is("Fana"));
List<Movies> movies = mongoTemplate.find(query, Movies.class);
The drawback of this query is that it may return duplicate results present in different documents, since more than 1 document may match this criteria. So you can add _id in the criteria like below:
Criteria criteria = Criteria.where('_id').is(movieId)
Query query = new Query().addCriteria(criteria)
query.fields().elemMatch("movies", Criteria.where("name").is("Fana"));
query.fields().exclude('_id')
List<Movies> movies = mongoTemplate.find(query, Movies.class);
I am excluding "_id" of the document in the response.
I have collection in following format.
{
id:____,
name:"Carlos",
city:"Mumbai"
},
{
id:____,
name:"Pravin",
city:"Mumbai"
},
{
id:_____,
name:"Gaurav",
city:"Ahmedabad"
}
I want whole document distinct by city. I tried the db.collection.distinct("city"). But it returns only distinct cities.
Current Output:
["Mumbai","Ahmedabad"]
Expected Output:
{
id:____,
name:"Carlos",
city:"Mumbai"
},
{
id:_____,
name:"Gaurav",
city:"Ahmedabad"
}
Above you can see there is only one record of "Mumbai". I need this kind of output.
Anyone know how we can get whole document with distinct in spring-mongodb?
You could try running an aggregation pipeline operation where you can include the the other fields inside the $group pipeline stage using the $first operator. Two examples that show this approach follow:
Mongo Shell:
pipeline = [
{
"$group": {
"_id": "$city",
"id": { "$first": "$_id" },
"name": { "$first": "$name" }
}
}
]
db.collection.aggregate(pipeline);
Spring Data MongoDB:
import static org.springframework.data.mongodb.core.aggregation.Aggregation.*;
MongoTemplate mongoTemplate = repository.getMongoTemplate();
Aggregation agg = newAggregation(
group("city")
.first("_id").as("id")
.first("name").as("name")
);
AggregationResults<OutputType> result = mongoTemplate.aggregate(agg,
"collection", OutputType.class);
List<OutputType> mappedResult = result.getMappedResults();
I am using cloudantDB and want to query a view which looks like this
function (doc) {
if(doc.name !== undefined){
emit([doc.name, doc.age], doc);
}
what should be the correct way to get a result if I have a list of names(I will be using option 'keys=[]' for it) and a range of age(for which startkey and endkey should be used)
example: I want to get persons having name "john" or "mark" or "joseph" or "santosh" and lie between age limit 20 to 30.
If i go for list of names, query should be keys=["john", ....]
and if I go for age query should use startkey and endkey
I want to do both :)
Thanks
Unfortunately, you can't do so. Using the keys parameter query the documents with the specified key. For example, you can't only send keys=["John","Mark"]&startkey=[null,20]&endkey=[{},30]. This query would only and ONLY return the document having the name John and Mark with a null age.
In your question you specified CouchDB but if you are using Cloudant, index query might be interesting for you.
You could have something like that :
{
"selector": {
"$and": [
{
"name": {
"$in":["Mark","John"]
}
},
{
"year": {
"$gt": 20,
"$lt": 30
}
}
]
},
"fields": [
"name",
"age"
]
}
As for CouchDB, you need to either separate your request (1 request for the age and 1 for the people) or you do the filtering locally.
I would like to run a bulk delete operation on a list of documents in MongoDB that have been selected by the user in the UI so I need to dynamically build a query that looks like the following (the or clause expands for every document selected):
{
$and: [
{
"contentType": "application/vnd.sometype"
},
{
$or: [
{
"metadata.name": "someName",
"metadata.version": "someVersion"
},
{
"metadata.name": "someOtherName",
"metadata.version": "someOtherVersion"
}
]
}
]
},
Fields: null,
Sort: null
Just now I'm using string concatenation to achieve this.
Is it possible to build this query with the Spring Data MongoDB Criteria Builder (org.springframework.data.mongodb.core.query.Criteria)?
Doesn't this work for you?
Criteria criteria = Criteria.where("contentType").is("application/vnd.sometype");
List<Criteria> docCriterias = new ArrayList<Criteria>(docs.size());
for (Document doc: docs) {
docCriterias.add(Criteria.where("metadata.name").is(doc.getName())
.and("metadata.version").is(doc.getVersion()));
}
criteria = criteria.orOperator(docCriterias.toArray(new Criteria[docs.size()]));
?
Here we need to build new query and embed the criteria to the built new query. And also, we have to create a list of criteria using some criteria for embed to the query. Here my example is providing a list of metadata and we don't know the name of parameter which will send for us. So, The solution is as given follow.
List<Criteria> criterias = new ArrayList<>();
for (MetaData metaData : newDoc.getMetaData()) {
Criteria dynamicCriteria = Criteria.where("metaData.key").is(metaData.getKey()).andOperator(Criteria.where("metaData.value").is(metaData.getValue()));
criterias.add(dynamicCriteria);
}
Criteria criteria = new Criteria().andOperator(criterias.toArray(new Criteria[criterias.size()]));
Query searchQuery = new Query(criteria);
List<Document> documents = mongoTemplate.find(searchQuery, Document.class);