Migration does not alter my table

问题

I just enabled migrations in my project and added a few fields to UserProfile:

[Table("UserProfile")]
public class UserProfile
{
    [Key]
    [DatabaseGeneratedAttribute(DatabaseGeneratedOption.Identity)]
    public int UserId { get; set; }
    public string UserName { get; set; }
    public string Email { get; set; }
    public string Description { get; set;}
    public DateTime? CreatedOn { get; set; }
    public DateTime? LastAccess { get; set; }
}

I Add-migration AddFieldsForUserProfile and it created:

    ...
    public override void Up()
    {
        AddColumn("dbo.UserProfile", "Email", c => c.String());
        AddColumn("dbo.UserProfile", "Description", c => c.String());
        AddColumn("dbo.UserProfile", "CreatedOn", c => c.DateTime());
        AddColumn("dbo.UserProfile", "LastAccess", c => c.DateTime());
    }
    ...

Update-database -verbose yielded this output:

Target database is: 'Hifi.Models.HifiContext' (DataSource: (localdb)\v11.0, Provider: System.Data.SqlClient, Origin: Convention).
Applying code-based migrations: [201303311011083_AddFieldsForUserProfile].
Applying code-based migration: 201303311011083_AddFieldsForUserProfile.
ALTER TABLE [dbo].[UserProfile] ADD [Email] [nvarchar](max)
ALTER TABLE [dbo].[UserProfile] ADD [Description] [nvarchar](max)
ALTER TABLE [dbo].[UserProfile] ADD [CreatedOn] [datetime]
ALTER TABLE [dbo].[UserProfile] ADD [LastAccess] [datetime]
[Inserting migration history record]
Running Seed method.

Apparently all went well, but after recieving an error that the coloumn CreatedOn does not exist, I looked into the database with the Server Explorer and indeed, all 4 coloumns are missing in my UserProfile table. What did I do wrong?

Edit

I found my error. Somehow I had two different mdf files aspnet-Hifi-20130330054424.mdf and Hifi.Models.HifiContext.mdf which had the same file size and I assumed both were necessary. My Server Explorer was using the aspnetxx.mdf and the database changes were made to HifiContext.mdf. Shame on me.

On a related note I had trouble correctly displaying a list of all registered users. It was always empty altough I could login flawlessly. Somehow for login aspnetxx.mdf was queried but my MemberListController queried HifiContext.mdf. After changing my connection string I had initially no registered users, new ones were added to HifiContext.mdf and the list worked properly. How did this happen?

回答1:

are you sure you're looking at the right Db?
it seems so though. Did you get any errors? Any special permissions etc.

My advice is to create a new connection - e.g. config and

<connectionStrings>
    <add name="HifiContext" connectionString="Data Source=MACHINE\INSTANCE;Initial Catalog=HiFi;Integrated Security=True; MultipleActiveResultSets=True" providerName="System.Data.SqlClient" />
</connectionStrings>`

...and backup your old just in case. i.e. recreate Db from scratch

If nothing works - try recreating if you just turned migrations on - no other ideas.

As for why the out-of-sync happened - hard to say for sure - but I'm guessing you had 'two connection strings' as well (or at some level).

Make sure that you connection string is 'named' the same as your dbcontext - or put connection at your at DbContext directly

. It is sometimes a problem, as it's not apparent what the EF/CF 'makes' as its default.

回答2:

call this method in your startup code to have the database recreated with the new fields:

public void CheckForDBChanes()
        {

            Database.SetInitializer(new DropCreateDatabaseIfModelChanges<Context>());
        }

来源：https://stackoverflow.com/questions/15730662/migration-does-not-alter-my-table