IQueryable vs LoadData

Radzen.Blazor Components
1

Hi,

Is there a resource that explains the "IQueryable" vs. "LoadData event" options for DataGrid Virtualization in more detail? I am new to virtualization and Entity Framework, so I want to understand how they work.

For example - do both methods use EF to get only the visible rows from the database? Or just LoadData? What is the difference ?

What are the advantages and disadvantages of each method?

Thanks,
Mike

2

There is no difference if binding to IQueryable, LoadData however can be used to plug custom filtering, sorting, etc.

3

So on your DataGrid -> Virtualization -> IQueryable support example -

When I scroll - I don't see a "loading" indicator when it queries the database for the next set of data.

Are all records loaded into the browser when the page is loaded? If so, is that not actually virtualization? My understanding was that virtualization means reading from the database only what is needed for display. Then when you scroll, it makes another request to the database. But I don't see that happening here - unless I'm missing something.

Thanks,
Mike

4

Virtualization is loading data on chunks when you scroll. Not sure what are your expectations however you can debug the demos locally to understand how everything works.

5

OK - loading data in chunks - is that from the database? Where does the "chunking" occur?

Thanks,
Mike