This has been raised several times, but it is just not practical to deliver a system with such slow binding. We have changed the DataGrid to GridView based on the recommendations, but to bind 15 records it takes 25 seconds, be it ListView or GridView.
Are we missing something in the UNO WinUI Solution which is causing this lag?
Thanks
Neeraj
Related
I'm fixing up a website which makes extensive use of the DevExpress ASPxGridView control to search against tables on a SQL Server. The results are then paged and parsed. Some of the search results can be fairly large and I suspect in those cases the built in pager for the ASPxGridView with the native SqlDataSource is prohibitively slow. On one query I observed the network traffic between the SQL Server and the IIS Server to be 1.5 GB over the span of just under a minute. Running the same query with an ORDER BY (SELECT NULL) OFFSET x ROWS FETCH NEXT y ROWS ONLY took a split second. Taking advantage of this SQL side paging on the control is another matter.
It seems my limitations and trade offs are the following:
The DevExpress ASPxGridView built in pager can't have the number of items explicitly set.
The independent DevExpress ASPxPager doesn't support client side events.
Replacing the SqlDataSource with LinqServerModeSource or XpoDataSource still has to parse the entire result set from the SQL Server to get the full count and will probably suffer the same performance issues.
I would like suggestions if any of following are possible solutions:
Is there any way to force the DevExpress ASPxGridView built in pager to use an external count?
Is there any way to wrap the DevExpress ASPxPager with say an Asp.Net UpdatePanel or DevExpress ASPxCallbackPanel to support client side events?
Can the LinqServerModeSource or XpoDataSource collect results from the SQL query as the ASPxGridView is paged with the total count provided by other means?
As mentioned here, it is possible to use SQL server side paging with ASPxGridView and ObjectDataSource by setting the ASPxGridView.DataSourceForceStandardPaging = true. DevExpress links to this example application on GitHub which is a bit broken, but easy to fix.
It works but, as they say:
[...] it is not possible to filter the ObjectDataSource datasource when the ASPxGridView.DataSourceForceStandardPaging is used.
Currently I'm trying to cheat the ASPxGridView by not setting DataSourceForceStandardPaging, but still use server side paging with ObjectDataSource: Perhaps it is possible to insert dummy rows into the result set in ObjectDatasource's SelectMethod, which then makes ASPxGridView "think" that is has retrieved all rows from the database, so that the pager can count the correct total rows number.
But I am not yet done with it... most probably the SubstituteFilterand CustomColumnSort events must then be handled to prevent the ASPxGridView from filtering and sorting the dummy records out.
whats are methods to keeping datasource for a gridview.
situation :
I have a query which can take 5 to 10 seconds (a lot of link on a lot of data).
The result is too big for a page so I have a paging on my grid.
But, every time I use the pageIndexChanged, I need to get the datasource again.
So I want to know how I can keep my datasource.
Is it possible? NOT by session.
It is possible, I have used a custom (server-side) viewstate provider to cache your datasource.
*Updated: There is a pretty good article on custom viewstate providers (with sample code) here: http://www.codeproject.com/Articles/8001/ViewState-Provider-an-implementation-using-Provide
However, I would strongly recommend improving your query to limit the data to that which the user really wants to see. Large grids that have many more rows than the user is truly interested in are unwieldy from memory, processor, bandwidth, and user-experience perspectives. Try to find a better way.
I did a task which geting more than 2 millions record from sqlserver and populate them in Asp.net GridView.
The problem is that, query taking more than 2 minutes in getting record while my query is now fully optimized.
when i move from one page to another by pagination it take again same time and hit server.
so i need a solution where its not take time during page movement or get only 50 or 100 record in each request.
Thanks,
Nauman
Use paging in GridView - check this link
Also adjust display property like display header with available visible cells to load the grid faster.
Its even better if you bind the grid data using jQuery and not from server side.
Use this link to get started
Instead of using GridView you can use repeater or even jQuery templates also with custom paging. that'll be even more fast.
if you are fetching 1000 records and displaying just 50 using pagination, this is really a waste. better to display 50 records each time, this would be much faster. go through the following link:Custom Paging in ASP.Net GridView using SQL Server Stored Procedure
it's problem on sqlserver...
optimization the data base,separate the database and the table
I have a gridview with about 300-400 rows that I use for reporting; it needs paging and requires sorting. My choice is between these two options: a) load the 300-400 in one query and let the gridview do the paging and sorting; b) handle the paging/sorting at the data source level. I know that b) is going to be better/faster/more efficient... In my context, I'm looking to get something done relatively fast; if I choose a), will the page seem incredibly/painfully slow?
Thanks.
Use the builtin functions of the GridView and load the whole data at one go. It wouldn't be worth the effort to implement paging in database(f.e. with RowNumber) when your number of records is such small, especially because you mentioned that you are looking for a fast solution. When you enable paging in GridView the performance will suffice.
read Scott Guthrie's excellent article about paging.
How to implement a data-result search page built with ASP.NET 2.0 and Atlas that can present hundreds of thousands of row results using the ASP.NET 2.0 GridView control. The results are formatted using a “paging” based UI model – where 15 results per page are displayed, and the user can skip from page to page to see their data. For kicks I also added support for editing and deleting each individual row.
Although 300-400 rows isn't a particularly large set of data, I would certainly vote for option B since it will definitely be more scalable. Once you start getting massive sets of data, loading all of it with one query and having the GridView handle the paging will end up being incredibly slow. The better option is to, like you said, only query the data you need for each page.
However, if you aren't going to have data sets larger than 300-400 records, you probably don't need to be too concerned about load times, but again, the key is in scalability.
Say I have 2 tables in a database, each with 100,000's of rows in detail and 10,000's of rows in the master 5 columns each, properly indexed and related. I want to have master/detail nested gridviews. What's the fastest architecture I could design in .net to do this? The largest result set on the master could be in the thousands (usually in the tens though) and the detail per records could be in the hundreds (usually in the single digits though). I'd like to be able to do a display all masters if possible.
The bottom line: bind to DataReaders, use Repeaters instead of GridViews, and turn off ViewState.
The design you're proposing is going to be pretty hard on your users (thousands of records, yikes), but you probably already know that.
If this is just for display and you want the absolute fastest architecture for Asp.Net, you should obtain an IDataReader for each data segment (master and child), sorted such that you can manually match child records while reading both resultsets in a forward-only fashion. (See Scott Mitchell's Why I don't Use DataSets in my ASP.NET Applications for some details about DataReader performance - as long as you aren't optimizing prematurely, it's quite good advice.)
Instead of using a GridView, I'd use a Repeater which has less overhead and lets you write more compact HTML (for a smaller payload to the client): bind the master IDataReader to that repeater. (I'm not sure whether you meant the GridView control, or just a conceptual grid - the basic architecture would be the same for a GridView)
Then add a handler to the Repeater.ItemDataBound that checks if the child data reader's current record matches. If it does, manually render your detail data for that master record.
Finally, you should also turn ViewState off, at least for the Repeater (preferably for as much of the page as possible), again so that the HTML payload is smaller.
If you're totally committed to nested GridViews, particularly to using a GridView to render the detail data, it's going to hurt the performance one way or another, because you'll have to either make many more database calls (to obtain discrete resultsets you can bind to) or you'll have to massage the detail data into an intermediary container.