VB.NET generated sql WHERE statement issue

[gaglia]

HI,

I'm having a problem using EF Core 7.0.9 in our VB.NET application.

We noticed that LINQ queries are translated differently when called from a C# project or from VB.NET

In VB.NET a SQL query is generated which is in our opinion incorrect, as it generates, for the same LINQ query, many more readings on the database than in C#. (Analysed with SQL profiler from 3 reads to 817)

The same LINQ query in Entity Framework 4.0 (We are converting our application to go from .NET 4.8 and EF 4.0 to .NET 7 and EF Core 7) in our same VB.NET application is generated correctly doing only 3 reads.

Attached I insert an example project where I highlight the problem by showing the sql code generated by EF.

App -> Project C# : All 3 queries are generated successfully with "correct" WHERE filter:

WHERE [g].[CodABI] = @$VB$Local_codABI_0 AND [g].[CodCAB] = @$VB$Local_codCAB_1',N'@$VB$Local_codABI_0 varchar(5),@$VB$Local_codCAB_1 varchar(5)

App.VB -> project in VB.NET: only the last query generates a "correct" sql, instead the other two generate this WHERE filter (causes many more readings on the database):

WHERE (CASE
WHEN [g].[CodABI] = @$VB$Local_codABI_0 THEN CAST(1 AS bit)
ELSE CAST(0 AS bit)
END & CASE
WHEN [g].[CodCAB] = @$VB$Local_codCAB_1 THEN CAST(1 AS bit)
ELSE CAST(0 AS bit)
END) = CAST(1 AS bit)',N'@$VB$Local_codABI_0 varchar(5),@$VB$Local_codCAB_1 varchar(5)

App.VB.Net48 -> project: all 3 queries are generated correctly

In the App project there is the CreateDatabase.sql script to create the sample database on which I generated the tests.

I await your feedback
A thousand thanks

Include provider and version information

EF Core version: 7.0.9
Database provider: Microsoft.EntityFrameworkCore.SqlServer
Target framework: .NET 7.0
Operating system: Win11
IDE: Visual Studio 2022 17.7.2

EFCoreTest.Solution.zip

[bricelam]

Duplicate of #27202

[gaglia]

Thanks so much for the feedback.

I saw that the report has been open for a long time, is there an idea of when the correction and release can be expected?

Because we are facing the migration of our application and we are a little worried by what has emerged from this analysis of the generated sql code.

Thanks again