EF Core HasDiscriminator with nullable discriminator

EF Core SQLite - Foreign Key nullable child insert (release)

I have a feeling it might be related to the null FK. Have you considered trying a "default" (i.e. All zeros in GUID format) entry for the nullable. And I believe you might need to specify when the FK is changed (comparable logic in this case) then you would need to indicate to EFC that the Entity's state is Unchanged /Modified / Added or Deleted..

EF Core Find breaks with Nullable Id

Looking at the code you've already linked: this cannot work, since the CLR gives you always the underlying type for a null-able instance. (Don't know why, had similar issues before...)...In code: ...typeof(int?) != ((int?)1).GetType().......Thus, comparing the type of the property (...int?...) and the type of the argument will always fail. You have...

How can I stop EF Core from creating a filtered index on a nullable column

Creating filtered index excluding ...NULL... values is the default EF Core behavior for ...unique... indexes containing nullable columns....You can use ...HasFilter... fluent API to change the filter condition or turn it off by passing ...null... as ...sql... argument:...entityBuilder.HasIndex(e => new { e.LevelId, e.Name, e.DeletedAt }) .IsUni...

EF CORE 2.0 Incompatible relationship (nullable foreign key)

ESUsersContact.Billing... class has a composite key. ...ESUsersContact... has to map both of the foreign keys. ...CompanyId... and Type. You can not refer only one column since ...ESUsersContact.Billing... has two columns for the key.

EF Core Inheritance issue (HasDiscriminator)

The problem is that all these properties are defined in the ...TransportRequest... class, but ...TransportRequest... is not specified to be an ...entity... (only the ...Request... and the final derived entities), hence EF Core assumes it's just a base class, and all derived classes properties are different....The ...Including & Excluding Types... s...

EF Core entity inheritance from different sources without discriminator

I would like to retain the inheritance....You can't (at least not in the way it is now). That's clearly indicated by the exception message - it says "cannot contain a mix" and does not provide you a suggestion....What you can do is to move your current ...User... class members to a new base ...non entity..., ...non query... type class and let both ...

EF Core Left Outer Join failing with nullable object must have a value

Credits go to Ivan Stoev, I am just providing a visible answer to this. The query syntax seems to be behaving a bit buggy, but in the end what did work was using only ...Navigation Properties..., which is much easier too. All I had to do was apply ....Count()... on the ...SolutionsView... navigation property, which will give you the count of views ...

Custom Discriminator on base type = null: "but does not have a discriminator value configured"

The error you get is originally because that the value of a ...Discriminator... cannot be null. But Actually there is another problem that makes it not work.... Every entity type in TPH (...Event... and ...Appointment...) must have a property as ...Discriminator.... ... If you don't specify any configuration for ...Discriminator..., a property name...

EF Core - How to group by a nullable column through multiple joins

There is nothing wrong with the way you compose the query. It's just one of the EF Core 2.2 query translation bugs/defects, because group by ...c.DId... works, bit the resulting key type is ...long?.... Also in EF Core 3.1 the query translates properly....The workaround for 2.2 is to use intermediate anonymous type for grouping key where you perfor...

Auto-generated FK relations in EF Core - how to made them non-nullable

Since the dependent entity has no reference navigation property on which to put ...[Required]... attribute or use C# 8 non nullable reference type (e.g. ...Parent... vs ...Parent?...), and has no explicit FK property with non nullable type (e.g. ...int... vs ...int?...), the only remaining option is fluent API....Relationship fluent API requires at...