Can anyone help with a MongoTemplate question?
I have got a record structure which has nested arrays and I want to update a specific entry in a 2nd level array. I can find the appropriate entry easier enough by the Set path needs the indexes of both array entries & the '$' only refers to the leaf item. For example if I had an array of teams which contained an array of player I need to generate an update path like :
val query = Query(Criteria.where( "teams.players.playerId").`is`(playerId))
val update = Update()
with(update) {
set("teams.$.players.$.name", player.name)
This fails as the '$' can only be used once to refer to the index in the players array, I need a way to generate the equivalent '$' for the index in the teams array.
I am thinking that I need to use a separate Aggregate query using the something like this but I can't get it to work.
project().and(ArrayOperators.arrayOf( "markets").indexOf("")).`as`("index")
Any ideas for this Mongo newbie?
For others who is facing similar issue, One option is to use arrayFilters in UpdateOptions. But looks like mongotemplate in spring does not yet support the use of UpdateOptions directly. Hence, what can be done is:
Sample for document which contain object with arrays of arrayObj (which contain another arrays of arrayObj).
Bson filter = eq("arrayObj.arrayObj.id", "12345");
UpdateResult result = mongoTemplate.getDb().getCollection(collectionName)
.updateOne(filter,
new Document("$set", new Document("arrayObj.$[].arrayObj.$[x].someField"), "someValueToUpdate"),
new UpdateOptions().arrayFilters(
Arrays.asList(Filters.eq("x.id, "12345))
));
Related
I have an array of interviewers (called interviewers) within a Mongo object. I am updating the name of an interviewer within the array. I have access to two strings, interviewer and oldInterviewer, and within the array I want to update the oldInterviewer value to be interviewer.
Currently, I am doing this in two queries - a .pull and then a .addToSet. Is there any way I can do this in one query, with a .set.
This is a Spring application and to do this I am using the Update() class.
My current code looks like this:
Update update = new Update().pull("interviewers", oldInterviewer)
bulkOps.updateMulti(query, update)
bulkOps.execute()
BulkOperations bulkOpsInsert = mongoTemplate.bulkOps(BulkOperations.BulkMode.UNORDERED, Interview)
Update addElement = new Update().addToSet("interviewers", interviewer)
bulkOpsInsert.updateMulti(secondQuery, addElement)
return bulkOpsInsert.execute().getModifiedCount()
Thanks in advance.
Good Morning.
I'm starting to learn some mongo right now.
I'm facing this problem right now, and i'm start to think if this is the best approach to resolve this "task", or if is bettert to turn around and write another way to solve this "problem".
My goal is to iterate a simple map of values (key) and vector\array (values)
My test map will be recived by a rest layer.
{
"1":["1","2","3"]
}
now after some logic, i need to use the Dao in order to look into db.
The Key will be "realm", the value inside vector are "castle".
Every Realm have some castle and every castle have some "rules".
I need to find every rules for each avaible combination of realm-castle.
AccessLevel is a pojo labeled by #Document annotation and it will have various params, such as castle and realm (both simple int)
So the idea will be to iterate a map and write a long query for every combination of key-value.
public AccessLevel searchAccessLevel(Map<String,Integer[]> request){
Query q = new Query();
Criteria c = new Criteria();
request.forEach((k,v)-> {
for (int i: Arrays.asList(v)
) {
q.addCriteria(c.andOperator(
Criteria.where("realm").is(k),
Criteria.where("castle").is(v))
);
}
});
List<AccessLevel> response=db.find(q,AccessLevel.class);
for (AccessLevel x: response
) {
System.out.println(x.toString());
}
As you can see i'm facing an error concerning $and.
Due to limitations of the org.bson.Document, you can't add a second '$and' expression specified as [...]
it seems mongo can't handle various $and, something i'm pretty used to abuse over sql
select * from a where id =1 and id=2 and id=3 and id=4
(not the best, sincei can use IN(), but sql allow me)
So, the point is: mongo can actualy work in this way and i need to dig more into the problem, or i need to do another approach, like using criterion.in(), and make N interrogation via mongotemplate one for every key in my Map?
Does anyone know if there's an easy way to negate a parse query? Something like this:
Parse.Query.not(query)
More specifically I want to do a relational query that gets everything except for the objects within the query. For example:
const relation = myParseObject.relation("myRelation");
const query = relation.query();
const negatedQuery = Parse.Query.not(query);
return await negatedQuery.find();
I know one solution would be to fetch the objects in the relation and then create a new query by looping through the objectIds using query.notEqualTo("objectId", fetchedObjectIds[i]), but this seems really circuitous...
Any help would be much appreciated!
doesNotMatchKeyInQuery is the solution as Davi Macedo pointed out in the comments.
For example, if I wanted to get all of the Comments that are not in an Article's relation, I would do the following:
const relationQuery = article.relation("comments").query();
const notInRelationQuery = new Parse.Query("Comment");
notInRelationQuery.doesNotMatchKeyInQuery("objectId", "objectId", relationQuery);
const notRelatedComments = await notInRelationQuery.find();
How I understand it is that the first argument is specifying the key in the objects that we are fetching. The second argument is specifying the key in the objects that are in the query that we're about to argue. And lastly we argue a query for the objects we don't want. So, it essentially finds the objects you don't want and then compares the values of the objects you do want to the values of the objects you don't want for the argued keys. It then returns all the objects you do want. I could probably write that more succinctly, but w/e.
Is there a way to restrict the "columns" returned from a Realm Xamarin LINQ query?
For example, if I have a Customer RealmObject and I want a list of all customer names, do I have to query All<Customer> and then enumerate the results to build the names list? That seems cumbersome and inefficient. I am not seeing anything in the docs. Am I missing something obvious here? Thanks!
You have to remember that Realm is an object based store. In a RDBMS like Sqlite, restricting the return results to a sub-set of "columns" of an "record" makes sense, but in an object store, you would be removing attributes from the original class and thus creating a new dynamic class to then instantiate these new classes as objects.
Thus is you want just a List of strings representing the customer names you can do this:
List<string> names = theRealm.All<Customer>().ToList().Select(customer => customer.Name).ToList();
Note: That you take the Realm.All<> results to a List first and then using a Linq Select "filter" just the property that you want. Using a .Select directly on a RealmResults is not currently supported (v0.80.0).
If you need to return a complex type that is a subset of attributes from the original RealObject, assuming you have a matching POCO, you can use:
var custNames = theRealm.All<Customer>().ToList().Select((Customer c) => new Name() { firstName = c.firstName, lastName = c.lastName } );
Remember, once you convert a RealmResult to a static list of POCOs you do lose the liveliness of using RealmObjects.
Personally I avoid doing this whenever possible as Realm is so fast that using a RealmResult and thus the RealObjects directly is more efficient on processing time and memory overhead then converting those to POCOs everytime you need to new list...
in my Spring MVC project i m using Hibernate, by using Criteria API i am applying Group BY and Order BY clause. Query get executed on DB successfully and it brings result also but its an array of Object--
Here is code of Criteria API
Criteria criteria = session.createCriteria(DashboardSubindicatorSubmission.class, "DashboardSubindicatorSubmission")
.setProjection(Projections.projectionList()
.add(Projections.sum("InputValue").as("InputValue"))
.add(Projections.groupProperty("fkAccademicYearId"))
.add(Projections.groupProperty("fkAssessmentPlanID"))
.add(Projections.groupProperty("fkSubindicatorID"))
.add(Projections.groupProperty("InputTitle")))
.addOrder(Order.asc("fkAccademicYearId"))
.addOrder(Order.asc("fkAssessmentPlanID"))
.addOrder(Order.asc("InputTitle"));
List<DashboardSubindicatorSubmission> dashboardSubindicatorSubmissionList = (List<DashboardSubindicatorSubmission>)criteria.list();
session.flush();
transaction.commit();
return dashboardSubindicatorSubmissionList;
I am casting criteria.list() to List<DashboardSubindicatorSubmission> but when i try to do dashboardSubindicatorSubmissionList.get(i) on controller it gives me exception java.lang.ClassCastException: [Ljava.lang.Object; cannot be cast to mkcl.accreditation.model.DashboardSubindicatorSubmission.
i come to know that, though i m casting it to List<DashboardSubindicatorSubmission> still its an list of object[] thats why i cant do dashboardSubindicatorSubmissionList.get(i) because it returns me object of DashboardSubindicatorSubmission. (Correct me if i am wrong)
So how can i convert my result into list of DashboardSubindicatorSubmission class?
Does setResultTransformer() helps me in this case?
You have two options. When you use projections, Hibernate doesn't know how to respect each field because it uses the name of each field to build objects and he doesn't know the names yet.
Thus, your first option is to name the fields grouped so that they match the names of object properties. This is necessary even if the string you use in projection is already the name of the object field. Something like:
.add(Projections.groupProperty("fkAccademicYearId"), "fkAccademicYearId") // same value
.add(Projections.groupProperty("fkAssessmentPlanID"), "other") // other value
The second option is to do what you yourself suggested, create your own implementation of ResultTransformer. I reckon this a interesting option if you want to extract other object of this query, as when you make a report.