Mongodb lookup when foreign field is an array of objects. Skip to main content.

Mongodb lookup when foreign field is an array of objects Schema({ user: { type: Schema. Learn more about Teams is a collection of object id's referencing my user schema / collection. 6 you cannot even do atomic updates of "nested arrays" and even with the changes that allow it, it is still "difficult" at best to do any query operations, and especially those involving joins and filtering. I know I can fetch users that have a certain item using {users. If the ref key is missing or it doesn't missing but the entity in collectionB is missing I get empty result from all of the aggregate query. Mongo playground: a simple sandbox to test and share MongoDB queries online. 3. 1 First: We add additional field to messages which contains converted string authorId to ObjectId() Second: We use this field as localField (in messages) to be compared with foreignField '_id' (in authors) MongoDB lookup when foreign field is an array. The sort() works at the document level and does not reorder arrays within the documents. The issue is that the collection 'properties' is having foreign field 'email' as a value in an array so i am not able to apply lookup on it. Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; About the company MongoDB lookup when foreign field and local field are array of objects. 0. Modified 5 years, 1 month ago. user works. MongoDB lookup array of objects by field and retain other fields in result-1. mongoplayground. MongoDB aggregation matching ObjectId against string. lookup({ from: 'users', localField: 'reviews. Connect and share knowledge within a single location that is structured and easy to search. – s7vr. Aggregate when local field is a key in array of object from another collection. I have users schema with people field containing viewers property which contains an array of ObjectIds as a reference of users collection itself for example { "username": "user1", "passwor Aggregation with $lookup and $unwind between two collections - MongoDB Loading Learn how to query an array and an array element or field, query on the array field as a whole, query if a field is in an array, and query by array size. I can convert one collection ObjectId to string with $ What I want to achieve is to lookup the author field and get the user data, but the problem is that the lookup I am trying to use only returns this to me: Code :. match condition on on foreign collection with lookup in Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; About the company Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; About the company The problem is that this only matches against the first object in the items array, and it overwrites other fields within the items scope, leaving just the things property, with the lookup of the first array. lookup with 2 matching key one in foreign document another in same foreign sub document array mongo. If the specified name already exists in the foreign document, the existing field is overwritten. in this second case solution of this post may This is my collection: I have collection color, so i want to join product with color and don’t know how. MongoDB lookup on an array of objects which contains (foreign) ObjectId as a key the product is inflated, but its an array instead of an object. Indexing array of references using mongodb multikey indexing method in mongoose. Mongo: 3. try localField:"parts" and foreignField:"_id" and see if it resolves correct. We are though not that happy with this solution and are considering removing these declarations and instead do the reference lookups manually. Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; About the company Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; About the company when i run aggregate lookup with bellow query, in new generated lookup array only one casts contents If in accordance with above casts array value aggregate lookup should return two casts content with two type. net Mongo playground. I have the nested array object and I need to lookup the field inside the array object. 6 and onwards, then the more expressive "sub-pipeline" is generally what you want to "filter" the results of the foreign collection before anything gets returned into the array at all. Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; About the company Visit the blog Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; About the company I want to lookup from an object to a collection where the foreignField key is embedded into an array of objects. This page provides examples of query operations on array fields using the For releases of MongoDB 3. users. Before MongoDB 3. @RaphaelDDL : Yes which ever is comfortable can be picked :-) this answer also merging Objects so no need to individually pass fields to reform fields, This uses loops concept to avoid exploding collection with high no. I'm trying to query mongoDB by joining two collections. _casts should contains two object not one object! Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; About the company I am working through a small example of my own based on the M121 course. $': 1}); MongoDB 3. "} { _id : 3, items : [ "pears", "pecans", "cherries Aggregation expressions accept a variable number of arguments. Types. 4, actually 3. author', }) Response : Any way to get the author's data in that field? Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; About the company Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; About the company Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; About the company Visit the blog An array of objects allows you to store multiple items in a single field, and it allows you to easily add, remove, and modify individual items within the array. of docs - unwinding on nested arrays can be an issue when your applications data grows overtime, if you can understand one loop In 2. But I want to fetch the actual item from the array, not the user. Learn about the $lookup aggregation stage, which performs left outer joins with collections in the same database, adding a new array field to each input document with The most common way to search through arrays of objects in MongoDB is to use a basic querying method by using the find() method. Consider not storing followers as an array of objects, but as an array of references: stats { followers [ followerId ] } Then, you can just populate whole followers array with lookup. Data structure: - loads (collection) - orders (collection) - costs (sub document)[ { co I have the nested array object and I need to lookup the field inside the array object. Mongodb 2 collection with collection array. It is possible to do a lookup on a DBref field within your aggregator, and you don't need mapreduce for that. details and the field you are left-joining on is _id: Specifies the name of the new array field to add to the foreign documents. Stack Overflow. But I'm not able to do that when the primary identifier is inside an array in the secondary collection. All of that said, it's not really a good idea to "nest arrays" with MongoDB. MongoDB lookup when foreign field is an array of objects. MongoDb: Match value on foreign collection. Hot Network Questions PSE Advent Calendar 2024 (Day 3): A cacophonic crossword Sharing own software with a restricted group of persons How to approach time series forecasting Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; About the company Specifies the name of the new array field to add to the foreign documents. Combine the result of (1) and (2) into an array. @mickl what if the foreignField is an array of objects, not just strings? in this case, what if favorites contained both the name and id? slot_divisions does not appear to be an array. However, when the argument is a single value, you can simplify your code by passing the argument directly without wrapping it in an array. I have: collection "shirts" { "_id" : ObjectId("5a797ef0768d8418866eb0f6"), Skip to main content. MongoDB aggregate match by array of ObjectIds. we are trying to match _id object to mId foreignfield which is not working. Match multiple values in array. For example, the following index definition configures Atlas Search to automatically index all dynamically indexable fields inside the Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; About the company Visit the blog I'd like to utilize its powerful array indexing, but I'm not sure if you can run queries on embedded arrays and return objects from the array instead of the document that contains it. Ok, Took me a bit but here it is. I'm using MongoDB, and I tried to do it with many pipeline steps but I couldn't find a way. For example, if you have a collection of users and each user has a list of friends, you could use an array of objects to store the list of friends for each user. Learn why MongoDB was selected as a leader in the 2024 Gartner® Magic MongoDB lookup when foreign field is an array of ids. I have a simple Appointments and Events collection and would like join and return all documents that are associated with a specific provider. ObjectId I'm trying to do this for days, but can't find any success. @albertyou2 I am facing the same issue, result is empty if I do conditional lookup on a foreign field which is present in array. For anyone new to MongoDB and isn't familiar with constructing MongoDB JSON query objects inside the find* methods, you can leverage the mongoose Query Builders. array value with: Get the first element of the field. It's a common "newbie" mistake to structure "nested arrays" since you Specifies the name of the new array field to add to the foreign documents. Ask Question Asked 5 years, 1 month ago. The foreign key is within the 'rels' array of objects (the _id is stored in rels. array array and add the newField field. i am hereby showing my attempt as below Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; About the company Specifies the name of the new array field to add to the foreign documents. What I want to achieve is to lookup the author field and get the user data, but the problem is that the lookup I am trying to use only returns this to me: Code :. actionType', foreignField: '_id', as: 'events. steevej (Steeve Juneau) December 21, 2021, 7:39pm 4 Specifies the name of the new array field to add to the foreign documents. but returned director casts content. In our case we know its going to be Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; About the company Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; About the company Specifies the name of the new array field to add to the foreign documents. How to Database Deploy a multi-cloud database Search Deliver engaging search experiences Vector Search Design intelligent apps with gen AI Check if the instock and the ordered fields are arrays. Learn how to query an array and an array element or field, query on the array field as a whole, query if a field is in an array, and query by array size. These are great for newcomers or to encourage consistent querying within your team. 5 for testing) in combination with Morphia where we use @Referenece on a couple of entities. How did you resolve this? I should add that while something along the lines of this { from: 'enumerations', localField: 'events. 2 you can also do this using the $ projection operator, where the $ in a projection object field name represents the index of the field's first matching array element from the query. I need to join these collections with field 'email' but due to having foreign field 'email' as a value in an array in 'properties' collections I am not getting results. Get all the elements other than the first element of the field. Mongoose, query a collection with a set of ObjectID Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; About the company Specifies the name of the new array field to add to the foreign documents. looking for mondodb docs. author', foreignField: '_id', as: 'reviews. author', }) Response : Any way to get the author's data in that field? Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; About the company Visit the blog actually it works but its not filling the company data inside companyData object, its filling the data inside promotionsData array item and overrides any exist field with the same name – Reda Khalaf Method 2 arrange data first and then lookup, while method 3 lookup first and then arrange data. Searching multiple fields in mongodb. Commented Feb 15, 2018 at 14:50. especially, when you are new to a community, this is something unavoidable. 5. The following returns the same results as above: db. 4. Though 2 and 3 looks similar, I think method 3 is faster than method 2. item_id: "1234"}. Appointment collection: { _id: ObjectId('62fd3e631d732145ed86adff'), imported: false, provider: Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; About the company I need to join entities from the same table 'entities' together. 2 assuming the collection that has the details is video. For example, we have an array of student_Info in our collection student which MongoDB Manual: code examples for query operations on array fields. . array array. If both fields are arrays, concatenate them: db items : "One or more fields is not an array. Actually, I thought that since it’s an array of objects it should be prefixed with an asterisk. MongoDB: Search in array. Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; About the company Set the field. Both local and foreign fields are of type ObjectId. Learn more about Teams So it checks local field productId is in foreign field array of products. The ideawas to provide a localField depending on one field in the retrieved object. Actually, the other answer is wrong. Share Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; About the company To index all fields in an embedded document including fields that Atlas Search doesn't dynamically index, define the fields in the index definition. How did you resolve this? If you want to do conditional lookup with the array field then first you need to unwind that array field as conditional lookup is not working like normal lookup. MongoDB Aggregation: How to put results from lookup into a nested array? Hot Network Questions What is the need for angle-action variables in describing integrable systems? Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; About the company We have had a similar issue as we use MongoDB (3. These arguments are normally passed as an array. The reason being, mongodb expects that multiple documents in the products table may match with this criteria, and hence by default puts all the docs in an array. "ObjectID('AAA')" is a string as is it surrounded by double-quotes. Is there anyone can help me ! You can do it with something like this in MongoDB 3. v2) to perform a query that populates them with data from the documents that they reference. I have two collections, fruit and salesman . Related. Viewed 3k times 1 . I want my query to return all fruit with comma separated salesman. 2 Update I want to query User and then lookup to get Books data, with specific userId and bookId but when if that user don't have Books, still return the User data with empty books or null. How to search for text or expression in multiple fields. you may have confused local and foreign fields. Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; About the company We have users from all backgrounds and at all levels and we are not psychics, so please bear with us and do not expect anyone to know everything about you at first glance. r). Is it possible with mongodb query or not? @albertyou2 I am facing the same issue, result is empty if I do conditional lookup on a foreign field which is present in array. 2. actionType' } Seems to make I have 2 collections, the first storing the animes watched by each user, their status etc: const listSchema = mongoose. For string faceting, Atlas Search counts string facets once for each document in the result set. Good Morning. This is not a duplicate of the linked question because the elements in question are not an array but embedded in individual objects of an array as fields. I am fully aware of how the query in the linked question should work, however that scenario is different from mine. in casts array value exists two type of casts, 1) writers and directors. items. they do not have anything on this. As I said, your choice of words, especially “tried everything” confuses us about your level of understanding. 1. MongoDB UNIQUE Field Constraint MongoDB findAndModify() Method MongoDB findOneAndUpdate() MongoDB findOneAndReplace() Guide MongoDB bulkWrite() Method Indexing Fields in MongoDB MongoDB Compound & Multikey Indexes MongoDB Full-Text Index Guide MongoDB: Manage Unused Indexes MongoDB Index Usage Stats MongoDB: Selecting I have two collections on which i have to do lookup query on ObjectId of both collections. I have these entities: // collectionA { key: "value", ref: SOME-OBJECT-ID } // collectionB { _id: SOME-OBJECT-ID key1: "value1" } I want that if ref exists in the collectionA entity, it will lookup for it on the collectionB and bring its data. 4. It would appear that you managed to name the keys "0" and "1" respectively. Search an array of objects in Mongo for any values contained in array. 4 What I tried. The local key is the _id of the local entity. I have an array of ObjectIds in my MongoDB documents and I'd like to use Go (specifically mgo. Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; About the company Visit the blog MongoDB lookup when foreign field is an array. You can do it like this: Working example. MongoDB lookup array of objects by field and retain other fields in result. color": "red"}, {_id: 0, 'shapes. find({"shapes. if not, from your given data, it is possible your parts array does not hold actual IDs but just some strings that look like some ID. Find documents matching multiple fields in an object array in MongoDB. The slots in the other document is an example of what Database Deploy a multi-cloud database Search Deliver engaging search experiences Vector Search Design intelligent apps with gen AI Stream Processing Unify data Ah, right, bookings. The new array field contains the matching documents from the foreign collection. 5. test. Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; About the company Your example will list all documents with their _id field and name array, sorted by the first name in each array. kix tlaxq rzmx wuabwnq noepo amvpizw vrpl hrjctr mwwon ekyrn