As per
https://marmelab.com/react-admin/Caching.html#optimistic-rendering
When navigating from a list to a single item the same record is reused, problem is that if computed fields are added only to the getOne dataProvider response (they would be too expensive for the list) these fields are empty.
How to fix this?
Not sure exactly why this is a problem to you because the missing fields will be loaded eventually after the getOne completes.
But if you really want to disable the cache in queries, you need to provide your own QueryClient and set it to disable the cache (probably by setting the cacheTime option to 0).
Hope this helps.
Related
Background:
I'm using DataTables in conjunction with a JS library called "Turbolinks", which basically turns your application into a Single Page Application (SPA) without all the overhead of using a true client-side framework. It is extremely useful for Ruby on Rails application performance.
There's a couple of headaches it introduces though - one is compatibility with DataTables. I've got it working pretty well by basically destroying any DataTable on a Turbolinks navigation, and then re-initializing it on turbolinks page load again. This method works well and seems to be the all-around accepted answer as to the best practice to get DataTables to work with Turbolinks.
Question:
On of the last features / finishing touches I'm trying to add to some of my applications is DataTable state saving. The issue I'm facing is that every time a table is destroyed/re-initialized on a page navigation, the...I'm actually not quite sure what to call it, but it looks like from inspecting the settings object on the stateSaveCallback - it looks like its the sInstance and/or the sTableId:
DataTables_Table_0
Then the localStorage key gets set as:
DataTables_DataTables_Table_0_/current_path: "{data: data}"
where current_path is whatever path/page you're on.
Then when it get re-initialized upon returning to the page, it gets set as DataTables_Table_1, and so on and so forth - so the state never gets correctly loaded.
Is there a way to override that ID (or some way to set the name of it in the stateSaveCallback / stateLoadCallback) so that it doesn't increase the last '0', '1', etc at the end of it? That way when the table is re-initialized, it will pull the saved state from just DataTables_Table/current_path?
The answer is to simply give the table an ID! Then DataTables won't assign it its own ID with the incrementing number and the saveState option just works.
Also, the destroy/re-init actually causes the server to get hit twice in the case of an AJAX table.
The better way to do it is to disable the turbolinks cache for any index pages with datatables. If not, you'll end up doing two requests to the server when only one is needed.
I'm using .take() and .skip() for paging with a table.
Now when I "insert" an entity into the database, I reload my table (new query). Now I would like to jump to this new object inside the table and highlight it.
Is there an elegant solution to find on what page the new object is and then use skip/take to jump to the correct page?
Edit:
Maybe Breeze/OData could natively support paging by allowing to specify a page-size in the query and which page to deliver (instead of using take and skip and calculating it on the client).
If this was the case, the parameter for "which page to deliver" could, instead of being an integer, also be a sub-query which would be executed on the resulting data before it gets "taked and skipped" to find out, on which page the object(s) are visible and use this as "page to deliver".
Edit 2:
Added the idea to Breeze UserVoice: https://breezejs.uservoice.com/forums/173093-1-breezejs-feature-suggestions/suggestions/6824937-support-paging-natively
It's an interesting idea, but I don't know of any really elegant solution to accomplish this. Conceptually, how would you expect this to work under the covers?
We have some strange problem here. We have feature event receiver, where we are creating custom fields -> content type -> list. After that, one default item is added. On my VM it was working just fine, but after moving into pre-prod environment, we got this strange behavior with no exception or error in logs.
First thing, item was created only sometimes, with no trace what happened. Mostly it was not created. I even experienced this: when I activated feature, I went to the list and so item there, but after refresh it was gone!
We tried to put there some Thread.Sleep() cycle (while debugging, item was in Items collection, but ItemsCount property of the list was always showing 0).
Now I am out of ideas what is wrong. It's not about execution time (maybe). Looks like, for some reason, SP is killing SPItem.Update before it is created for real and we don't know why. Any help is really welcome!
When you try to access sharepoint items from code and not have admin permissions to update/ delete them then set website website.AllowUnsafeUpdates = true; property
//Set AllowUnsafeUpdates = true to update the database / sharepoint list from code.
FormWeb.AllowUnsafeUpdates = true;
NewItem.Update();
FormWeb.AllowUnsafeUpdates = false;
you code should be like this to make changes in the list.. when you adding item to list.
Use Update statement in same manner when you accessing list and updating its data.
Check whether you updating the list correctly.. There may be some SharePoint security issue.
Reference Link:
http://blogs.msdn.com/b/infopath/archive/2010/04/01/add-items-to-a-sharepoint-list-using-managed-code.aspx.
You can check this [SPSecurity.RunWithElevatedPrivileges][1]
[1]: http://msdn.microsoft.com/en-us/library/microsoft.sharepoint.spsecurity.runwithelevatedprivileges.aspx , link, link
you can check that what is going over there by adding your events in sharepoint..
Check this post and debug it..
http://developmentsolutionsjunction.blogspot.com/2011/06/adding-events-and-eventhandlers-in.html
so I was finally able to find out where the problem was. After deeper study and trying that and this I found out that there was a third party feature. It was adding event to each created list and was deleting everything what wasn't consistent with CT defined by company. This is weird and I don't really understand why somebody wants this. But ok, they pay, their rules.
So if you encounter such problem, try also this possibility.
However, I also leard few things during this, e.g. if you are working with SP instances from web scope, use web scoped features, not site ones, also, SP has a nasty habit to silent som exceptions. Also, if you e.g. take instance of SPWeb from event properties, it doesn't necessarily means it is already created. It takes some time, also, Update() itself is a thing that DB has to perform. Sometimes it's better to alsways check if you really have instance and if not, threadsleep for a while.
Have you used .Update() method in your code??
Is it okay to change that thing if we are not using the cache anyway?
To repeat, we're not supposed to change the fetchrequestcontroller request only if we do not use the cache right?
If I am displaying a table based on user search and the search change, should I create a whole new fetchrequestcontroller?
The documentation states "You must not reuse the same fetched results controller for multiple queries unless you set the cacheName to nil". It also states you should delete the cache if modifying the fetch request. I often use two different caches depending on the application. You can read more about NSFetchedResultsController here and it's delegate here.
Currently I am struggling with a Entity Framework issue. I have a wcf service that sits on top of the ef framework, and allows queries to the framework. At some point the user is able to request a file from the framework. The files are referenced by solution entries, so when you request a file from a solution, the reference is loaded to gain access to the file store.
That all works fine, but from that point onward, whenever you do another query that returns that solution entry, the whole file gets attached to the return result. I need some way of detaching or unloading the reference, such that the result entries will only contain an unloaded reference to the file store again.
I have tried to create a new context and query that context to retrieve information from, but when I do that, the entity in the original context is also changed.
I have tried to detach the entity from the original context and then query from the new context. That does not work either.
I have found one way of doing this. For all the non file-download queries, I detach the result entity, and send that over the wire. I am not sure if that is the best way to go about it though.
I hope someone might be able to provide some insight, thanks for the effort.
The issue you are experiencing is probably do to Change Tracking, which is on by default.
Possible Solution:
Disable Change Tracking with MergeOption.NoTracking
using (MyEntities _context = new MyEntities())
{
_context.Widgets.MergeOption = MergeOption.NoTracking;
return _context.Widgets.ToList();
}
This article may help to point you in the right direction on how to handle this issue if the solution above does not work.
I struggled with a similar issue recently. The problem was the result of the context maintaining a reference to the object I was using (obviously). Every time I made a change to an object of the same type, even when obtained with a new context (so I thought), the object was being changed.
With help from one of my peers, we determined the context was hanging around due to the way I was registering it with my IoC container (lifestyle per web request). When I changed the lifestyle to transient (which definitively provided a new instance) then changes to objects of the same type were unaffected.
Hope this helps.