23,248 questions
1
vote
0
answers
29
views
Strongly typed id in EF Core while projecting to some model
I try to query Postgresql DB on models with strongly typed ids and project to a model.
Cannot understand why query doesn't work.
It throws this exception:
Unhandled exception. System....
0
votes
0
answers
15
views
Error creating new instance of ef core context in new Inventor 2025 addin
I am creating an addin for Inventor 2025 using its own vb.net addin template.
It needs to interact with a sql server database (load drawing info and saving parts lists).
When I create the new instance ...
0
votes
0
answers
28
views
How to force a many to many relationship to be queried as OUTER JOIN in Entity Framework
I have this structure in SQL Server:
Look at the expanded tables.
CampoAdicionalPorPersona table is a navigation table between Persona and CampoAdicional (many to many relationship).
When I do this ...
- 4,554
1
vote
0
answers
26
views
EF Core migration - nullable property gets turned into a non-nullable column
I have a model class OverAllStatus with this property:
[Column("OverallStatusID")]
[StringLength(50)]
public string? OverallStatusId { get; set; }
However, in the ContextModelSnapshot, the ...
- 11
0
votes
0
answers
30
views
EF Core does not change the table schema when the API is at runtime
I'm developing a multi-tenant ASP.NET Core Web API project and I use EF Core 8 as my ORM and SQL Server. The project supports several tenants and I need to create the databases at run time and change ...
- 21
-1
votes
1
answer
54
views
ASP.NET Core & EF Core : concurrency exception not thrown despite working rowversion
This is part of my method which creates reservations of books:
var book = await _context.Books.FirstOrDefaultAsync(b => b.Id == id);
if (book == null || !book.IsAvailable)
{
return ...
3
votes
2
answers
64
views
Does Entity Framework Core support queries based on a table of custom values?
I'm using a T-SQL query like
SELECT
WeekStart,
(SELECT COUNT(DISTINCT UserId)
FROM Logins
WHERE Timestamp >= WeekStart
AND Timestamp < DATEADD(wk, 1, WeekStart)) ...
- 2,525
0
votes
1
answer
52
views
Entity Framework query filter is not being applied
I am applying a query filter globally on all entities that inherit from EntityBase class:
// filtering not deleted items
Expression<Func<EntityBase, bool>> filterExpr = eb => !eb....
- 19
0
votes
0
answers
14
views
Understanding EF Core Add-Migration
I tried finding this the source code to investigate how it finds the context but no luck with source code so far.
Here is a my project structure:
EXE App containing EF Core Tools
Class library ...
- 401
1
vote
1
answer
26
views
Data Logic at Facade level
I have 2 Db's with their own projects, data services and controllers.
We have methods for them at the facade level which can use either Db.
I have a situation where I need to write something to both ...
1
vote
1
answer
63
views
Comparing decimals within a LINQ query using a SQLite-database fails with operators but works with .CompareTo
In my SQLite database, I have a table foo that contains a column bar that is of data type decimal. I want to retreive all rows, where the value of bar is > 100.
If I try to execute the query like ...
- 1,667
1
vote
1
answer
23
views
Resolving TPH Inheritance and Migration Issues in Entity Framework Core with Multi-Project Architecture
I’m working on a multi-project architecture with models and data access layers in separate .csproj files (These are Class Libraries.) Using EF Core 8 and TPH inheritance, I encounter the following ...
- 11
0
votes
1
answer
43
views
Using a single DBContext with a model for multiple schema generated at runtime in EF Core
Considering a sample application with the data structure:
Calculations: Id, Value
The application should update the database structure at runtime to add a new table recognized by schema. Then it ...
- 141
0
votes
2
answers
28
views
how to set entity's property order to mapping migrations dbscript columns order?
1.I have a BaseModel class:
public class BaseModel : BaseDeletedModel
{
[Key, Column(Order = 0), MaxLength(50), Required]
public string ID { get; set; }
}
public class BaseDeletedModel
{
[...
- 3
1
vote
2
answers
45
views
Query jsonb array in postgresql table with EF Core
I would like to return all the rows that contains a price higher than 123:
// Entity Table1
[Column(TypeName = "jsonb")]
public List<NewPrice> HistoryPrices { get; set; }
public class ...
- 667
-1
votes
0
answers
38
views
This method or property cannot be called on Null values [duplicate]
I get this error:
fail: Microsoft.EntityFrameworkCore.Query[10100]
An exception occurred while iterating over the results of a query for context type 'Infraestructure.Data.AppDbContext'.
System.Data....
0
votes
1
answer
32
views
Why does EF Core's DbContext.Update() keep original child entities in DB and at other times doesn't?
My ASP.NET Core Web API app uses SQL Server and I have the following service registered in Microsoft.DependencyInjection as a scoped service:
public class UpdateOperation<TEntity, TDto>(
...
- 3
0
votes
0
answers
16
views
Inconsistency between Powertools for Lambda (.NET) and EF Core interceptor
For example, I have a EF Core method like this
[Tracing(CaptureMode = TracingCaptureMode.Error)] // AWS Powertools for tracking traces
public async Task<TEntity> FindAsNoTrackingAsync(...
0
votes
0
answers
37
views
Map JSON column to both string and strongly-typed data with EF Core
An entity:
public class Person
{
// both of these properties should refer to same jsonb column
public string ContactsJson { get; }
public Contacts Contacts { get; }
}
public class Contacts
{
...
- 19.6k
0
votes
1
answer
56
views
EF Core FirstOrDefault returns null even if entity exists
I am facing an issue where I cant fetch an entity when using .FirstOrDefaultAsync() with a GUID as the primary key.
If I fetch all entries first and then run .FirstOrDefault it works.
The entity in ...
- 245
0
votes
2
answers
76
views
How can I add multiple conditions in a LINQ Select to return values based on an enum?
I'm working on a LINQ query where I need to select values from a data source based on the value of an enum (ConversationRole). I want to return different user IDs based on whether the ConversationRole ...
- 13
0
votes
0
answers
56
views
How to exclude records with empty collection in linq query [duplicate]
I have 3 tables in postgres DB (docker postgres:14.1-alpine).
public class House
{
public Guid Id { get; set; }
public virtual ICollection<Flat> Flats { get; set; }
public ...
0
votes
0
answers
42
views
How can I implement Role Based Access Control in an ASP.NET Core Web API?
I am currently working on improving my Web API skills.
I have tried to implement them using the IdentityRole class as well as the Identity User but I don't seem to get the hang of it. I am honestly ...
- 125
0
votes
1
answer
35
views
Can I insert ID 0 in MySQL with EF Core HasData?
I'm writing a server for a client that I do not control. I'm using HasData to seed the database with static information that the client refers to by ID. The client uses 1-based numbering for almost ...
- 10.3k
0
votes
0
answers
42
views
change made by _context.SaveChangesAsync written to DB, but on next page, changes are not visible until refresh [closed]
I work on a .NET 6 project based on Blazor and EF Core, which saves a lot of work for me. However, I face a problem: the app has many pages.
On the first page, the central service (containing all the ...
- 1
1
vote
1
answer
36
views
Relation 'Logs' Does note exist (EF Core / PostgreSQL Migration)
Stumped about what's going on here. My LogEntity appears to be implemented no differently than my TenantEntity, and they have the same implementation in my ApplicationDBContext.
I am doing a code-...
- 2,114
1
vote
1
answer
66
views
Include function does not work in EF Core when I inject the generic repository
I implemented this pattern so many times before, I created a context, after that I created a generic repository, like this:
public class GenericRepository<T> : IGenericRepository<T>
where ...
- 19
0
votes
1
answer
40
views
Checking for presence in database and then adding element in Entity Framework causes unique PK error
I have the following code:
foreach (var species in list.Species.ToList())
{
if (context.Species.FirstOrDefault(x => x.PK_Species == species.PK_Species) == null)
{
context.Species....
- 2,998
0
votes
0
answers
38
views
Entity Framework Core can't find main web project when we set it to run on 32-bit
I have been helping update an old DLL into a REST API. The old DLL had a plethora of references to other DLL's, including one we need that was written in Visual Basic.
This DLL also needs to run in 32-...
- 86
2
votes
1
answer
75
views
After update to .NET 9: Services for database providers 'SqlServer', 'InMemory' have been registered in the service provider
Upgraded from .NET 8 to 9 and I now get an error in my integration tests:
System.InvalidOperationException
Services for database providers 'Microsoft.EntityFrameworkCore.SqlServer', 'Microsoft....
- 3,075
0
votes
0
answers
25
views
GOD Methods or reusing small? [closed]
public class Book
{
[Key]
public int BookId { get; set; }
public string Title { get; set; } = string.Empty;
public string Description { get; set; } = string.Empty;
public string ...
0
votes
1
answer
48
views
Entity framework navigation properties remain null until saving to database
Say I have a basic example of a data tree to save in the database:
class TreeModel {
int id;
virtual Collection ParentNodes;
}
class ParentNode {
int id;
virtual Collection TreeModel;
...
- 935
1
vote
0
answers
27
views
EF Core finding attribute via convention that I don't want it to
I have a class library representing my EF Core 9 database. That library includes a NuGet package of attributes that are set on the model. It's used to configure the generation of PUML files at ...
- 10.2k
0
votes
0
answers
16
views
EF Core with XUnit "The requested operation cannot be completed because the connection has been broken."
When I run multiple unit tests that use the same API, I am randomly getting this error:
The requested operation cannot be completed because the connection has been broken.
Here are the exception ...
- 2,204
1
vote
1
answer
60
views
EF Bulk Extensions is really slow for me, but why?
I have a C# console app on .NET 6.0, using EF Core 6.0.35.
I am making an API call to get data (from Geotab) that I filter, transform and insert into my DB. Each insert is 1000 to 2000 records.
My ...
- 1,680
0
votes
0
answers
21
views
Cannot Use Multiple Context Instances Error in ABP Framework with CommonDbContext Configuration
I'm working using ABP framework and Entity Framework and I have a simple query like this:
// Ensure everything uses the same DbContext (CommonDbContext)
var organizations = await ...
- 475
0
votes
1
answer
35
views
How to avoid materializing a query prematurely in Entity Framework Core
I am working with the ABP Framework using C# and Entity Framework Core, and I have the following query:
public async Task<ListResultDto<GetLinkedOrganizationsDto>> ...
- 475
0
votes
2
answers
85
views
EF Core throws a tracking exception when updating entities using AutoMapper
I'm using EF Core against a SQL Server database in a Blazor web app (on .NET 9) with Identity, and I am using AutoMapper to convert between the database entities and the DTOs that get sent out of and ...
- 9,380
1
vote
0
answers
53
views
EF Core SaveChanges error after explicit transaction
I have a code, which tries to do a certain first set of operations inside an explicit transaction, and then the rest of operations just normally.
The transaction goes okay, and gets disposed. Then ...
- 347
0
votes
0
answers
33
views
EF Core inherited overriding property not saved with the value given to property
I have a VoucherDefinition class and 4 types derive from that, named:
PublicStaticVoucherDefinition
PublicRandomVoucherDefinition
DedicatedStaticVoucherDefinition
DedicatedRandomVoucherDefinition
...
- 3,010
-1
votes
0
answers
48
views
I get an error like that "Format of the initialization string does not conform to specification starting at index 0."
I'm trying to write my first API to connect to SQL Server. I have been following all the steps from a tutorial, but I only obtain this error. I have heard this error is because the wrong connection ...
- 1
0
votes
0
answers
33
views
EF Core Add Migration Error: Duplicate Seed Entity for 'AdditionalProductSubType'
I am encountering an issue when running the Add-Migration command in my EF Core project. The command fails with the following error:
System.AggregateException: One or more errors occurred. (The seed ...
- 1
0
votes
0
answers
23
views
GroupBy problem in .NET 3.1 .First()' could not be translated. Either rewrite the query in a form that can be translated,
Models look like this, I made them shorter for explanation
public partial class Child : Entity<int>, IAggregateRoot
{
public Lrp Lrp { get; set; }
public int LrpId { get; set; }
...
0
votes
2
answers
74
views
Blazor Quickgrid - how to add a row counter when using Virtualise
Using Blazors Quickgrid. I would like to show a row number for the items.
They are 'ApplicationUser' Items. (The id is a guid)
It looks like this:
<div class="grid" tabindex="-1">...
- 766
0
votes
1
answer
24
views
Dapper logging when using connection from EF Core DbContext
I have a legacy code that is using dapper's QueryAsync() on DbContext's dbconnection:
var connection = _context.GetConnection();
await connection.QueryAsync<Guid>(query, parameters);
How do I ...
- 27.2k
0
votes
1
answer
335
views
What are the implications of suppressing EF Core's PendingModelChangesWarning?
I'm working on an ASP.NET Core Web API using Entity Framework Core. As I tried to update my database I get this error:
An error was generated for warning
'Microsoft.EntityFrameworkCore.Migrations....
- 125
0
votes
0
answers
27
views
Entity Framework Core : nullable FK update child issue
Some question has not group so I set FK as a optional field. When I am trying to update group, I get an error. If GroupId is required, then there is no problem.
public class Question
{
[Key]
...
- 1
-1
votes
0
answers
45
views
Entity Framework Core C# recursive load of the parent child relationship lazy loading [duplicate]
I have a table in my database with a parentID column referencing the same table's ID key column. Each entry in that table can have a parent - record from the same table and list of children - also ...
0
votes
0
answers
34
views
Missing field after a document Insert/Update in mongodb through C#
I have a migration script that tries to insert data into mongodb. I build the document object and insert it into a collection. The main document object has a bson element that has a recursive/nested ...
- 161
0
votes
0
answers
46
views
ASP.NET Core Identity Framework + EF Core Postgres + snake case table names
I would like to configure ASP.NET Core Identity Framework + EF Core on Postgres with lowercase snake_case table names. As it currently stands my IdentityDbContext looks like this:
using Microsoft....
- 143