Suppose i have company collection, and company has members, members of company may be registered in my application as a user or may be not a registered user. So now how i can store member details such as first_name, last_name, id of member in case of registered members inside company.members. I have something like this inside company:
Suppose company has two member: member A is a registered member in my application and i have his/her id, profilePic, and member B is not registered, so i have only his/her first_name, last_name.
As usual there is more than 1 answer for this question and it depends on how your application will be used, the simplest way is:
1) on company document set a array with your users straight way, this is good for university projects and to proof of concept
In a real world solution I'd split the documents in 2 or more collections, so:
2) on company document set an array with the object id o the user collection, this is useful in case you need to work often with the company or user collection, a separate collection could be used for each registered or unregistered users
3) big trucks need big engine, so if you really need to work hard with company and user documents, like including new user, companies or even changing them from a group to another, registering a new account and them including them to your system in a way often I would suggest using a collection just for the groups
MongoDB does an amazing jog when we talk about reading operation, so the idea is getting its work easier for that, if you split the writing job mongo will work better on that, so managing little chunks of data each time is best
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It's my first time working with FireStore. I'm working on a ridesharing app with Flutter that uses Firebase Auth where users can create trips and offer rides similarly to BlaBlaCar, where other users can send requests to join a ride. I’m having difficulty not only deciding the potential collections and paths to use, but also how to even structure it.
For simplicity at this stage, I want any user to be able to see all trips created, but when they go to their “My Rides” page, they will only see the rides that they’ve participated in. I would be grateful for any kind of feedback.
Here are the options I’ve considered:
Two collections, “Users” and “Trips”. The path would look something like this:
users/uid and trips/tripsId with a created_by field
One collection of “Users” and a sub-collection of “Trips". The path seems to make more sense to me, which would be users/uid/trips/tripId but then I don't know how other users could access all the rides on their home feed.
I'm inclined to go with the first option of two collections. Also very open to any other suggestions or help. Thanks.
I want any user to be able to see all trips created, but when they go
to their “My Rides” page, they will only see the rides that they’ve
participated in
I make the assumption that participating in a ride is either being the author or being a passenger of the ride.
I would go for 2 collections: one for users and one for trips. In a trip document you add two fields:
createdBy with the uid of the creator
participants: an Array where you store the author's uid and all the other participants uids (passengers)
This way you can easily query for:
All the rides
All the rides created by a user
All the rides for which a user is a participant, using arrayContains.
(Regarding the limit of 1 MiB for the maximum size for a document I guess this is not a problem because the number of passengers of a ride shouldn't be so huge that the Array fields size makes the document larger than 1 Mib!)
Note that the second approach with subcollections could also be used since you can query with collections group queries but, based on the elements in your question, I don't see any technical advantage.
i am building a small web app with MERN, i have a collection that holds "name, email, password, avatar url, and date" and i am going to add to the users some info like a "bio, hobbies(array), "visited countries(array), and another array"
question is, should i create a diffrent model for the users info, and add owner field that refers to the other model?. or should i put all of them there,
also i might add the following and followers option in the future.
The user's info should be in the user collection, I could see there is no reason to have a separate collection for it. If you want to reduce the responses from listing users, you could use populate to remove unnecessary fields.
Regards to the following and followers, I think there are 2 approaches:
Adding a new field which used to store id and necessary metadata (name, avatar) of users to the existing collection
Create a new collection which is a combination of users and users they are following, or are followed. You then could use Virtual to get this information from the User collection.
Personally, I prefer the first approach although it requires more effort to maintain the list to be accurate. E.g remove an item out of the list when your follower stops following you.
so I'm working with a database that has multiple collections and some of the data overlaps in the collection . In particular I have a collection called app-launches which contains a field called userId and one called users where the _id of a particular object is actually the same as the userId in app-launches. Is it possible to group the two collections together so I can analyze the data? Or maybe match the the userId in app-launches with the _id in users?
There is no definit answer for your question Jeffrey and none of the experts here can tell you to choose which technique over other just by having this information.
After going through various web pages over internet and mongo documentation and understanding the design patterns used in Mongo over a period of time, How I would design it depends on few things which I can try explaining it here in short.
if you have a One-To-One relation then always prefer to choose Embedding over Linking. e.g. User and its address (assuming user has only one address) thus you can utilize the atomicity (without worrying about transactions) as well easily fetch the records without too and fro to bring other information as in the case of Linking (like in DBRef)
If you have One-To-Many relation then you need to consider whether you can do the stuff by using Embedding (prefer this as explained the benefits in point 1). However, embedding would help you if you always want the information altogether e.g. Post/Comments where your requirement is to get the post and all of its comments by postId let say. But think of a situation where you need to get all the comments (and it related posts) which contains some specific tags in comments. in this case you should prefer Linking Because if you go via Embedding route then you would end up getting all the collection of comments for a post and you have to filter the desired comments.
for a Many-To-Many relations I would prefer two separate entities as well another collection for linking them e.g. Product-Category.
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I'm not much of a backend guy and even worse when it comes to MongoDB, however, I've been taken with Meteor.js so I'm giving it a try as I play around.
I'm creating a project management/ticketing app and would like your opinion on the data model design. In my app you create a ticket, assign other team members to the ticket and allow people to access it and manipulate the data like a todo list, attachments, comments, etc. Pretty basic.
From my research, it appears that a normalized data model with references makes sense. In that case, is a good model:
A collection for all my users.
A collection for tickets (each ticket/project its own document) with a field for team members in which I insert them into an array using a reference. Then I'd have fields for comments, todos, etc.
Or would this be best:
A collection for all my users.
A unique collection for each ticket with a field for team members kept in an array.
Sorry if this seems rather basic. I'm taking the MongoDB University classes for Node, so I hope I don't have to rely on too many basic questions for too long.
Thanks everyone!
You should store each ticket/project in its own document in a single collection (the first option).
If you give each ticket its own collection you have no effective way to index and query tickets.
I have two collections - Tickets and Users. Where a user can have one to many tickets. The ticket collection is defined as follows
Ticket = {_id, ownerId, profile: {name}}
The ownerId is used to find all tickets that belong to a specific person. I need to write a query that gets me all users with no tickets.
How can i write this query without having to loop through all users, checking if the userID shows up in any Tickets?
Would a bidirectional storage cause me any performance problems ? For example, if i were to change my users collection and add an array of tickets: [ticketID, ticketID2, ...]?
I'd go with the array of tickets being stored in users. As far as I know, Mongo doesn't really have a way to query one collection based on the (lack of) elements in another collection. With the array, though, you can simply do db.users.find({tickets:[]}).