Skip to main content

EFCore - Scaffold-DbContext how to use

EFCore versions, we don't have GUI to manage the DB-entities & dbContext like we used to have with EF6 (or EF5/4 version). With EFCore we've the Scaffold-DbContext command which helps us to create entities & DB context from our DB-objects. 

Let's see how to use Scaffold-DbContext:

Assume we're connecting with SQL Server so after creating a sample project you'll have to install EFCore related libraries as mentioned below. 

Install entity-framework-core for SQL Server, at this time 3.1.9 is the latest stable version 

  •  Microsoft.EntityFrameworkcore 
  •  Microsoft.EntityFrameworkCore.SqlServer 

To use Scaffold-DbContext, following two NuGet packages are required

  • Microsoft.EntityFrameworkCore.Tools 
  • Microsoft.EntityFrameworkCore.Design

Let's say we've two DB tables (e.g. dbo.Employees & dbo.Users ) 



Now let's see how to use Scaffold-DbContext to create c-sharp entities for those two tables:


Open Package manager console

Visual Studio => Tools => NuGet Package Manager => Package Manager Console



Your package manager console will appear like this:



Now run Scaffold-dbContext command like this:

Here in the connection string, either you can use integrate security or user-name/password combination. 
  • To create a separate directory for dbContext use -ContextDir option
  • To create custom dbContext name use -Context option 

the command is something like this. 

Before executing this command make sure you've selected the "Default project" where you want to create the entities & DB context (e.g. TestWebApp.DataAccess)  

Scaffold-DbContext 'Data Source=localhost;Initial Catalog=TestDatabase;Integrated Security=True' 
Microsoft.EntityFrameworkCore.SqlServer 
-OutputDir Models -Tables "Dbo.Employees","Dbo.Users" 
-ContextDir "MyContextDir" -Context MyTestContext


Atest successful execution of this command your "Package manager console" will be like this. 


And in your project, you can observe the related entities for your db-objects & your context 






Labels:

Comments

Post a Comment

Popular posts from this blog

EFCore - Collate function

Search in SQL server query is generally case insensitive (by default or based on database level collation). Suppose we have an employees table with a row having first-name column value as "My-First-Name", so if we want to do the case-sensitive search we have to explicitly use the related collate: In EF 5 (currently in Release Candidate version [RC.2.20475.6]) Collate function got introduced which helps us to use our specific collation based search.  C# with EF5 code sample: var employeeCaseSensitiveSearch = _dbContext.Employees .Where(x => EF.Functions.Collate(x.FirstName, "Latin1_General_CS_AS") == "my-first-name") .FirstOrDefault(); A related database query will be something like this: T-SQL: Case sensitive search (use specific collation e.g.: Latin1_General_CS_AS) SELECT * FROM dbo.Employees AS e WHERE e.FirstName Collate Latin1_General_CS_AS = 'my-first-name' Some of the useful CSharp function which g...
Post a Comment
Read more

EFCore - Parallel db call on same dbContext

Practically there are multiple instances when we want to do parallel DB call which will save us some time. Like if we want to get a few employees details as well as users detail and if both entities are independent of each other better to go with a parallel call to fetch the details.  With the growing ORM usage and enhanced & optimized framework of like EFCore, in most of the application (related to C# development), we generally prefer to use EFCore. With EFCore if we try to use the same DB context to do parallel db call we are getting an error (... different thread using the same DbContext....). Because dbContext call is not thread-safe Parallel DB call on the same dbContext:  Code snipped: which will throw an error private void DbCallWithParallelCallOnSameDbContext() { try { var employeesTask = _dbContext.Employees.ToListAsync(); var usersTask = _dbContext.Users.ToListAsync(); ...
Post a Comment
Read more

How to install Zen-coding plugin

As a web-developer, irrespective of the technologies (java, c-sharp, python, php e.t.c.…), we used to write CSS code to make our web-pages looks good if not at least we’re involved in write html codes. What if there is some tool to whom you give some instruction and that tool generates a good, well formatted html tags for you. These kind of coding is possible and known as “ Zen coding ” and there are lots of plug-in available from different vendors. We’re going to  discuss the steps to install this “zen-coding” plugin for “visual studio, eclipse, sublime-text & notepad++ in next few lines. Follow the below steps to install "zen-coding" plugin based on your editor.  Steps to install zen-coding plugin for (visual studio, eclipse, sublime-text,notepad++) -- -- For Visual Studio 1. Go to "Tools" -> "Extensions and Updates" 2. It'll open the "Extensions and Updates windows"    Select online form Left hand menu items ent...
Post a Comment
Read more