DbMigrator running occurred warning in 4.1.0-rc.2

[gerryge]

Abp version 4.1.0-rc.2
User Interface: MVC
Database provider: EF Core

How to reproduce:

1. Run cmd "abp new Acme.BookStore --preview"
2. Run Acme.BookStore.DbMigrator and warning occurred

I changed the MultipleActiveResultSets in Default connection from true to false, then the warning disappeared.
"Default": "Server=(LocalDb)\MSSQLLocalDB;Database=BookStore;Trusted_Connection=True;MultipleActiveResultSets=true"
I also tried the v3.3.2 and v4.0.2 start templates, there's no this warning even MultipleActiveResultSets value is true.

Below is the detail info, I would like to know why this happened, Thank you.

[18:03:50 WRN] Savepoints are disabled because Multiple Active Result Sets (MARS) is enabled. If 'SaveChanges' fails, then the transaction cannot be automatically rolled back to a known clean state. Instead, the transaction should be rolled back by the application before retrying 'SaveChanges'. See https://go.microsoft.com/fwlink/?linkid=2149338 for more information. To identify the code which triggers this warning, call 'ConfigureWarnings(w => w.Throw(RelationalEventId.SavepointsDisabledBecauseOfMARS))'.

[real-zony]

Hi @gerryge, This warning was introduced in EF Core 5.0.1.(abp 4.1.x) For details, please refer to

• https://github.com/dotnet/efcore/releases/tag/v5.0.1
• https://github.com/dotnet/efcore/pull/23305/files#diff-8b3dd7645d9d7ac7e65062c2db7948e3553cb149750e5b76ff6e338ffa359e2d

[maliming]

@GameBelial Should we remove MultipleActiveResultSets=true in ConnectionStrings?

[real-zony]

@maliming This problem is caused by the introduction of the SavePoint feature in EF Core 5.0.1, which is the default behavior in EF Core 5.0.1. I think in our default template, MultipleActiveResultSets=true should be removed (for SQL Server).
If you need to disable the SavePoint feature, you can refer to this Issue (dotnet/efcore#23269).