Crud Operations in Entity Framework Codefirst in MVC 4 Using MySql Database

Question

To do CRUD operation I am adding controller and datacontext in scaffolding Options i have received this error

unable to retrieve metadata unable to cast object of type system.data.entity.core.objects.objectcontext to

This is my Model

namespace MvcMySql.Models
{
public class Code
{
 [Key]
    public int StudentID { get; set; }
    public string StudentName { get; set; }
    public string Address { get; set; }
    public string Email { get; set; }
    public string City { get; set; }
}
public class DatabaseContext : DbContext
{
    public DatabaseContext()
        : base("ConnectionString")
    {
    }
    protected override void OnModelCreating(DbModelBuilder modelBuilder)
    {
        modelBuilder.Entity<Code>().HasKey(p => p.StudentID);
    }
    public DbSet<Code> CodeFirsts { get; set; }
 }
}

My web Config

 <connectionStrings>
<add name="ConnectionString"connectionString="server=10.10.30.164;uid=demouser;password=welcome;database=demo"
providerName="MySql.Data.MySqlClient"/>
</connectionStrings>

 <system.data>
  <DbProviderFactories>
  <remove invariant="MySql.Data.MySqlClient" />
  <add name="MySQL Data Provider" invariant="MySql.Data.MySqlClient" description=".Net Framework Data Provider for MySQL" type="MySql.Data.MySqlClient.MySqlClientFactory, MySql.Data, Version=5.0.0.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d" />
</DbProviderFactories>
</system.data>
<entityFramework>
<defaultConnectionFactory type="System.Data.Entity.Infrastructure.LocalDbConnectionFactory, EntityFramework">
  <parameters>
    <parameter value="v11.0" />
  </parameters>
</defaultConnectionFactory>
 <providers>
  <provider invariantName="System.Data.SqlClient" type="System.Data.SqlClient.SqlProviderServices, EntityFramework.SqlServer" />
  <provider invariantName="MySql.Data.MySqlClient" type="MySql.Data.MySqlClient.MySqlProviderServices, MySql.Data.Entity.EF5, Version=5.0.0.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d"></provider>
</providers>

I cant identify where the error occurs this message i got while doing crud operations

EF6 has some issues with mvc 4. Either use mvc5 or use EF5. Follow this tutorial. http://www.asp.net/mvc/overview/getting-started/getting-started-with-ef-using-mvc/creating-an-entity-framework-data-model-for-an-asp-net-mvc-application — Nikitesh, Feb 19 '15 at 07:22
I am able to reproduce your issue with EF5. Restarted VS and build sln but problem persist. — SBirthare, Feb 19 '15 at 07:30
If you have section in web.config, remove it. I will add details as answer. — SBirthare, Feb 19 '15 at 07:41
MySQL is try to use EF5 instead of EF6. Try to change the type provider to something like — jlvaquero, Feb 19 '15 at 07:43
@DhasarathanT - Did you tried removing the provider as I suggested in my answer below? Does it work? — SBirthare, Feb 19 '15 at 07:48
System.Data.SqlClient.SqlProviderServices is EF5. System.Data.Entity.SqlServer.SqlProviderServices is EF6. You are mixing EF versions. In MS SqlServer you are trying to use EF6 and in MySql you are trying to use EF5. — jlvaquero, Feb 19 '15 at 07:52
@Dhasarathan T you are right. You are not mixing EF version in web.config. But it seems that VS do. Check the error popup namespaces. — jlvaquero, Feb 19 '15 at 08:11

score 0 · Answer 1 · edited May 23 '17 at 12:09

I was able to reproduce this issue locally. Then in order to solve it I searched "unrecognized element 'providers' entity framework" on Google as it was the error given on the message box.

The first link suggested me to remove parameter section but it was not present in my web.config file.

I reviewed my web.config files from other projects and found that It does not have a <providers> section in <entityFramework>.

In my current web.config I found it is there (due to downgrade to EF5 from EF6). Providers are introduced from EF6, read here.

Current web.config has:

  <entityFramework>
    <defaultConnectionFactory type="System.Data.Entity.Infrastructure.SqlConnectionFactory, EntityFramework" />
    <providers>
      <provider invariantName="System.Data.SqlClient" type="System.Data.SqlClient.SqlProviderServices, EntityFramework.SqlServer" />
    </providers>
  </entityFramework>

I removed the provider section and build the solution. Then tried adding the controller using scaffolding and bingo... it worked this time... Now my web.config looks like below:

  <entityFramework>
    <defaultConnectionFactory type="System.Data.Entity.Infrastructure.SqlConnectionFactory, EntityFramework" />
  </entityFramework>

@DhasarathanT - EF5 does not use provider. Something got mismatched in your configuration (may be due to downgrading to EF v5). Did you removed both the provider or just one for "System.Data.SqlClient"? — SBirthare, Feb 19 '15 at 07:52
sir i have removed both the provider and added entity framework what you have given sir — Dhasarathan T, Feb 19 '15 at 07:53
Nah, try keeping what you have got in original and just remove one provider for "System.Data.SqlClient". — SBirthare, Feb 19 '15 at 07:55

Crud Operations in Entity Framework Codefirst in MVC 4 Using MySql Database

1 Answers1