Entity Framework Uniqueness of Complex Object reference

Working with Entity Framework and Complex object can be challenging. For example, they must be defined even if in your code you set them as null. Another limitation of complex object is that you cannot have two of them referencing the same object. You will get the following error when saving: The entity of type […]

How to boost caching performance to cache Entity Framework object

Entity Framework objects are dangerous for caching because of their nature to keep references to object. If you have an object that contains a list of object that can contain back the initial object, you come in a scenario where you have a infinite deepness of reference. While this is not a problem in memory, […]

How to diagnostic slow code with Visual Studio

During the development of one feature, I noticed the performance to be very slow in some scenario. It was not obvious at first because the task was to simply update a user profile. The user profile in question is stored in a single table. It’s a pretty straight forward task. Before persisting the data, some […]

Dapper.Net coexistence with Entity Framework and caveats

Dapper.Net is a micro ORM (objection relational mapping) that StackOverFlow is using. It’s open source and it still maintained by the team, mostly by Marc Gravell who is a top 5 users in StackOverflow too. The project I am working on is getting slowed down by Entity Framework (EF) since few months and the introduction […]

Entity Framework Many to Many Relationship

The theory for many to many relationship is simple: you map two entities with key that you define on each side and Entity Framework generate the table that you have assigned the name with. Something like the code below works perfectly. The problem occurs when you want to save entities later. The problem is is […]

Entity Framework Complex Type and its Tracking

Entity Framework has something called complex type. They are classes that does not have unique identifier. They are used has a subset of an entity. For example, you can have an Address class that you want to have inside another class but do not want to have to have a table for the Address. This […]

Why I do not recommend any more Entity Framework as your ORM

If you follow that blog or know me than the title may shock you a little. Even if you do not know me, you might think I am crazy. Entity Framework (ef) is THE framework used in enterprise and it THE Microsoft’s ORM. It is not that I haven’t try to like it. I posted […]

Entity Framework (EF) modifying an instance that is already in the context

If you set an entity state to modify without having this one loaded and you save everything, than you have no problem. However, if you got the entity from a previous load, this one is inside the local context which can raise the following exception. Attaching an entity of type ‘Model.Entities.Users.ApplicationUser’ failed because another entity […]

Create an Index for you Entity Framework Index

Either you are working with a field that require a fast access or if the field is used as reference in some case, you will need to create an Index. Unfortunately, Entity Framework does not offer a quick way to do it. To tell Entity Framework to generate the Sql Index on the column, you […]

Never use Primitive Type for any Entities

I see in a lot of system an abuse of primitive types. Instead of using a class for an entity, the use of primitive is used. Often, when additional needs is required, additional primitives are used which duplicate. Here is some basic example: The problem is obvious, the Item class should not be in a […]