Update entity class in ASP.NET Core Entity Framework

Question

I have created the model from existing database using Entity Framework in ASP.NET Core.

Here is the model of the Market table

public partial class Market
{
        public Guid MarketId { get; set; }
        public string City { get; set; }
        public string CityF { get; set; }
        public string Name { get; set; }
        public string NameF { get; set; }
        public int SortOrder { get; set; }
        public bool IsActive { get; set; }
}

However, I have change the MarketId datatype to int in the database. Now I want to update the model.

Found some link but this link create the entire model again https://learn.microsoft.com/en-us/ef/core/get-started/aspnetcore/existing-db

How can I update the model without the creating new model and using the connection string in appsettings.json?

Deferred

You can use Scaffold-DbContext command with -force flag. This way you can force scaffolding to overwrite existing model files. – Geller

why not just change MarketId to int? – Equilibrist

Manually changing is not the best option. – Deferred

@sanket - can you please provide me the example – Deferred

@sanjaisy this is sample command - Scaffold-DbContext "<ConnectionString>" Microsoft.EntityFrameworkCore.SqlServer -t <tablename> -f replace ConnectionString & tablename – Geller

Also note, you will need to do this anytime you make a change in the DB like column added or removed or changed... When you force a scaffold update you will loose any modification you have made to the model file not that I can think of why anyone would do that. – Sublieutenant

@sanjaisy Did u tried with Scaffold-DbContext command? – Geller

@Geller - Yes it worked thanks – Deferred

@sanjaisy great :) but if you come across any other option please do share here. – Geller

Answer 1

To Update entire dbcontext use the below command. link for more details

"Build failed" on Database First Scaffold-DbContext

Scaffold-DbContext -Connection "Server=(local);Database=DefenderRRCart;Integrated Security=True;Trusted_Connection=True;" -Provider Microsoft.EntityFrameworkCore.SqlServer -OutputDir RRStoreContext.Models -context RRStoreContext -Project RR.DataAccess -force

To update from Azure Connection and local Connection

Scaffold-DbContext "Server=<Server Name>,1433;Initial Catalog=<Database Name>;Persist Security Info=False;User ID=<user id>;Password=<password>;MultipleActiveResultSets=False;Encrypt=True;TrustServerCertificate=False;Connection Timeout=30;" Microsoft.EntityFrameworkCore.SqlServer -OutputDir Entity -context <Context Name> -Project <project Name> -force

To create the new Context

Scaffold-DbContext "Server=<Server Name>,1433;Initial Catalog=<Database Name>;Persist Security Info=False;
        User ID=<User Id>;Password=<Password>;MultipleActiveResultSets=False;Encrypt=True;TrustServerCertificate=False;Connection
        Timeout=30;" Microsoft.EntityFrameworkCore.SqlServer -OutputDir <Dir Name>

Deferred

How is this the correct answer? The questions is about updating a single Entity, the answer updates the entire dbContext. – Unwatched

@Unwatched - Yes, you are correct it doesn't update the single entity It just replaces the single entity along with other entities. – Deferred

Looks like your initial question is tracked as a feature request for EF here github.com/aspnet/EntityFrameworkCore/issues/831 Maybe you want to add this to your answer? – Unwatched

Answer 2

One option is-

You can use Scaffold-DbContext command with -force flag. This way you can force scaffolding to overwrite existing model files.

sample command -

Scaffold-DbContext "<ConnectionString>" Microsoft.EntityFrameworkCore.SqlServer -t <tablename> -f

Replace ConnectionString & TableName as per your requirements.

Geller

This really helped Thanks – Locular

This also works in ASP.NET Core 2.0. It will automatically generate a context file within the project root, if the context file is elsewhere. However, generated code for the new table can easily be moved from OnModelCreating and the extra context removed. – Analyze

How to do the same programmatically? – Immunology

@SagarPatil You can auto generate a context with: Scaffold-DbContext "Server=tcp:"SomeAzureConnectionString";Initial Catalog=(YoutDataBaseName);User ID=(YourUser);Password=(YourPassword);Trusted_Connection=False;Encrypt=True;" Microsoft.EntityFrameworkCore.SqlServer -OutputDir Models -f – Acrogen