I have a "problem" with RTK Query, and how it works.
Each request I've made lost the data, because of removeMutationResult, so I have to assign the data to the other part of the redux-store.
And here is my question: should I assign data from API requests to the other part of the redux store, or should I try to eliminate the removeMutationResult action?
Related
I have a MESSAGERECAP collection which includes a unique id for each message, the id of the receiver of the message, the id of the sender and the message itself. In my application, when the user clicks on a friend to chat with him, I want the chat activity to start with the list of messages they have both sent.
I did this but obviously it does not give the desired result :
Query query = messageRef.orderBy("mssgId",Query.Direction.DESCENDING);
// with messageRef a reference to the MESSAGERECAP collection
Here is an overview of my database
You are getting the whole list because you are not filtering the data, just ordering it. If you check the Querying documentation for Firestore, also provided by #FrankVanPuffelen on the comments of your question, you can see that you have to use .where() to filter the data that you want to retrieve.
Also, as pointed out by #Jay in the comments, you can use Compound Queries to create a logical AND on your query to retrieve the data you want.
So if you do something like:
messageRef.where("senderId", "==", [currentUserId])
.where("receiver_id", "==", [receiverUserId])
.orderBy("mssgId",Query.Direction.DESCENDING)
When you execute this query you will get all the messages sent by the current user to the receiving user of the correponding id.
I've been using redux-crud, and really like it. I'm still very new to Redux itself, so the following question may seem a bit noob.
I'm at the point where I want to fetch just a single record freshly from the server when I enter the edit form for it. I can't rely on the record that might have been previously fetched into the state, to be the most accurate representation of it for editing purposes.
Based on my current understanding, it doesn't seem that redux-form is suited to fetching singles, rather it seems to suggest that I pull the record for edit out of the collection of records already in the state (previously fetched with the out of the box crud actions and reducers).
I have a type of record called Providers.
Am I right to say that I'm going to have to create a separate set of fetch actions and reducers that are suited to singular fetching?
So where Redux Crud would give me PROVIDERS_FETCH_SUCCESS, I would then need to go on and implement PROVIDER_FETCH_SUCCESS in a singular fashion? Or is there a simpler way out of the box with Redux Crud that I'm not seeing clearly?
Thanks!
redux-crud will manage updating items for you when you need to fetch individual entities. actionCreatorsFor and reducersFor both take optional secondary arguments to specify what
reduxCrud.actionCreatorsFor('providers', {key: '_id'});
reduxCrud.Map.reducersFor('providers', {key: '_id'});
You can then mark the action as "replace" to replace existing items that have matching key fields;
fetchSuccess(providers, {replace: true});
Or
fetchSuccess([provider], {replace: true});
I am building a chat engine using firebase in unity. I want to differentiate between the existing data and all the new data that gets added into the database. There is method once in web sdk of firebase which helps in differentiating between old and new data, is anyone aware if we have something similar on unity
There is no direct way to do this, one way that is a workaround is to add a timestamp value in all the entries maintained in the database and each time one subscribes for the new data we make use of the OrderByValue|OrderByKey and StartAt to do the same.
In the beginning value for StartAt will be 0 but post that whenever a child gets added we can update the StartAt value to that so that the next time client subscribes for the childAdded, it will only receive data post the last child.
I have a search function and currently what I'm doing is, subscribe to my collection each time the search parameters change like this :
Meteor.subscribe('job_search', searchParams).ready();
My question is, do we really have to do this? When fetching the data I use the search params. Will subscribing to all the data at once load all the data and reduce the performance of the app?
The subscription itself doesn't fetch the data, but it can act as a filter. The helper does the fetching whenever the data changes or a reactive query parameter changes. As long as your helper query doesn't fetch all the data you should be ok.
In my application I'm pulling back a user's "feed". This contains all of that user's activities, events, friend requests from other users, etc. When I pull back the feed I'm calling various functions to filter the request along the way.
var userFeed = GetFeed(db); // Query to pull back all data
userFeed = FilterByUser(userFeed, user, db); // Filter for the user
userFeed = SortFeed(userFeed, page, sortBy, typeName); // Sort it
The data that is returned is exactly what I need, however when I look at a SQL Profile Trace I can see that the query that is getting this data does not filter it at the database level and instead is selecting ALL data in the table(s).
This query does not execute until I iterate through the results on my view. All of these functions return an IEnumerable object.
I was under the impression that LINQ would take all of my filters and form one query to pull back the data I want instead of pulling back all the data and then filtering it on the server.
What am I doing wrong or what don't I understand about the way LINQ evaluates queries?
If GetFeed returns an IEnumerable, FilterByUser will receive an IEnumerable. When it calls some LINQ operator, i.e. Where, it will use the IEnumerable Where, which will start to ask for information, which will eventually download the entire table. Change the type of GetFeed to IQueryable to make sure that IQueryable's LINQ operators are called instead, which will keep delaying the query.