[DataGrid] EF Core Adapter - A second operation was started

[miguelhasse]

Pull Request

📖 Description

DataGrid with Paginator using IAsyncQueryExecutor for Entity Framework fails with the following error:
"A second operation was started on this context instance before a previous operation completed. This is usually caused by different threads concurrently using the same instance of DbContext."

🎫 Issues

fix: A second operation was started in DataGrid with EF Core #801

📑 Test Plan

Create a Blazor Server project that uses EF to connect a DataGrid component to a large database table, using IQueryable and pagination. Then quickly browse through pages to check there is no "second operation was started" exception. Ideally this should be done using integration tests using something like Testcontainers.

✅ Checklist

General

• I have added tests for my changes.
• I have tested my changes.
• I have updated the project documentation to reflect my changes.
• I have read the CONTRIBUTING documentation and followed the standards for this project.

Component-specific

• I have added a new component
• I have added Unit Tests for my new component
• I have modified an existing component
• I have validated the Unit Tests for an existing component

[miguelhasse]

microsoft

@microsoft-github-policy-service agree

[bryansjenks]

I'll just note that we have this problem all over and if this fix addresses it; that would be really helpful.
Thanks everyone for your hard work on this project!
-Bryan

[miguelhasse]

@bryansjenks I've provided a working sample in the following branch https://github.com/miguelhasse/fluentui-blazor/tree/adventureworks-server-sample/examples/AdventureWorks