Code First Migrations and initialization error

Question

I\'m unsure about how to use the code first migration feature. In my understanding it should create my database if it\'s not existing already, and update it to the latest sc

Answer 1

I was able to replicate your problem using SQL CE, as well as using EF code first using the code above.

The strange thing is that when I used your code as is, the first time, it worked perfectly. In order to have your issue arise, I had to actually delete the _MigrationHistory table in my .sdf file.

By deleting the .sdf file (I realize this might not be an option in your case, but I'll address that farther down) The next time it ran, it created the migration table - but it still didn't work quite properly. If you notice, at step 12 it's finally creates the table.

-- statement #1 SELECT [GroupBy1].[A1] AS [C1] FROM (SELECT COUNT(1) AS [A1] FROM [Dummies] AS [Extent1]) AS [GroupBy1]

-- statement #2 SELECT [GroupBy1].[A1] AS [C1] FROM (SELECT COUNT(1) AS [A1] FROM [__MigrationHistory] AS [Extent1]) AS [GroupBy1]

-- statement #3 WARN: System.Data.SqlServerCe.SqlCeException (0x80004005): The specified table does not exist. [ __MigrationHistory ]

-- statement #4 SELECT [GroupBy1].[A1] AS [C1] FROM (SELECT COUNT(1) AS [A1] FROM [__MigrationHistory] AS [Extent1]) AS [GroupBy1]

-- statement #5 WARN: System.Data.SqlServerCe.SqlCeException (0x80004005): The specified table does not exist. [ __MigrationHistory ]

-- statement #6 SELECT [GroupBy1].[A1] AS [C1] FROM (SELECT COUNT(1) AS [A1] FROM [__MigrationHistory] AS [Extent1]) AS [GroupBy1]

-- statement #7 WARN: System.Data.SqlServerCe.SqlCeException (0x80004005): The specified table does not exist. [ __MigrationHistory ]

-- statement #8 SELECT [GroupBy1].[A1] AS [C1] FROM (SELECT COUNT(1) AS [A1] FROM [__MigrationHistory] AS [Extent1]) AS [GroupBy1]

-- statement #9 WARN: System.Data.SqlServerCe.SqlCeException (0x80004005): The specified table does not exist. [ __MigrationHistory ]

-- statement #10 begin transaction with isolation level: Serializable

-- statement #11 CREATE TABLE [Dummies] ( [DummyId] [int] NOT NULL IDENTITY, [test] nvarchar, [addThis] nvarchar, CONSTRAINT [PK_Dummies] PRIMARY KEY ([DummyId]) )

-- statement #12 CREATE TABLE [__MigrationHistory] ( [MigrationId] nvarchar NOT NULL, [CreatedOn] [datetime] NOT NULL, [Model] [image] NOT NULL, [ProductVersion] nvarchar NOT NULL, CONSTRAINT [PK___MigrationHistory] PRIMARY KEY ([MigrationId]) )

-- statement #13 INSERT INTO [__MigrationHistory] ([MigrationId], [CreatedOn], [Model], [ProductVersion]) VALUES ('201208101940587_InitialCreate', '2012-08-10T19:40:59.055', 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

-- statement #14 commit transaction

-- statement #15 SELECT [GroupBy1].[A1] AS [C1] FROM (SELECT COUNT(1) AS [A1] FROM [Dummies] AS [Extent1]) AS [GroupBy1]

Which fixes the problem by creating the table in the right place:

Once I did this, the next time the code ran, everything ran perfectly again.

-- statement #1 SELECT [GroupBy1].[A1] AS [C1] FROM (SELECT COUNT(1) AS [A1] FROM [__MigrationHistory] AS [Extent1]) AS [GroupBy1]

-- statement #2 SELECT TOP (1) [c].[ProductVersion] AS [ProductVersion] FROM [__MigrationHistory] AS [c]

-- statement #3 SELECT [GroupBy1].[A1] AS [C1] FROM (SELECT COUNT(1) AS [A1] FROM [__MigrationHistory] AS [Extent1]) AS [GroupBy1]

-- statement #4 SELECT [Extent1].[MigrationId] AS [MigrationId] FROM [__MigrationHistory] AS [Extent1]

-- statement #5 SELECT [GroupBy1].[A1] AS [C1] FROM (SELECT COUNT(1) AS [A1] FROM [__MigrationHistory] AS [Extent1]) AS [GroupBy1]

-- statement #6 SELECT [GroupBy1].[A1] AS [C1] FROM (SELECT COUNT(1) AS [A1] FROM [__MigrationHistory] AS [Extent1]) AS [GroupBy1]

-- statement #7 SELECT TOP (1) [Project1].[C1] AS [C1], [Project1].[MigrationId] AS [MigrationId], [Project1].[Model] AS [Model] FROM (SELECT [Extent1].[MigrationId] AS [MigrationId], [Extent1].[CreatedOn] AS [CreatedOn], [Extent1].[Model] AS [Model], 1 AS [C1] FROM [__MigrationHistory] AS [Extent1]) AS [Project1] ORDER BY [Project1].[CreatedOn] DESC

-- statement #8 SELECT [GroupBy1].[A1] AS [C1] FROM (SELECT COUNT(1) AS [A1] FROM [__MigrationHistory] AS [Extent1]) AS [GroupBy1]

-- statement #9 SELECT TOP (1) [Project1].[C1] AS [C1], [Project1].[MigrationId] AS [MigrationId], [Project1].[Model] AS [Model] FROM (SELECT [Extent1].[MigrationId] AS [MigrationId], [Extent1].[CreatedOn] AS [CreatedOn], [Extent1].[Model] AS [Model], 1 AS [C1] FROM [__MigrationHistory] AS [Extent1]) AS [Project1] ORDER BY [Project1].[CreatedOn] DESC

-- statement #10 begin transaction with isolation level: Unspecified

-- statement #11 insert [Dummies] ([test], [addThis]) values (null, null);

select [DummyId] from [Dummies] where [DummyId] = @@IDENTITY

-- statement #12 insert [Dummies] ([test], [addThis]) values (null, null);

select [DummyId] from [Dummies] where [DummyId] = @@IDENTITY

-- statement #13 insert [Dummies] ([test], [addThis]) values (null, null);

select [DummyId] from [Dummies] where [DummyId] = @@IDENTITY

-- statement #14 insert [Dummies] ([test], [addThis]) values (null, null);

select [DummyId] from [Dummies] where [DummyId] = @@IDENTITY

-- statement #15 commit transaction

-- statement #16 SELECT [GroupBy1].[A1] AS [C1] FROM (SELECT COUNT(1) AS [A1] FROM [Dummies] AS [Extent1]) AS [GroupBy1]

If dropping the entire SDF and letting it recreate is not an option, here's what I did to get it back.

Create a connectionstring in your appconfig (I realize you're probably wanting dynamic connection strings that's why it's in your Code, but this should be a one time thing). My connection string looked like this:

Change the constructor of your Context so that it will use the connection string:

public MyContext()
    //: base(string.Format(@"DataSource=""{0}""", "MyContext.sdf"))
    : base("MyContext")

All of this is necessary so you can run some commands in Package Manager Console, so that it will re-create the table. Open up package manager console, and run this command:

add-migration initial -ignorechanges

Next, run the program - it will throw some warnings, but then it will create the table for you, and populate it. After that, you can change your constructor back and I had no more issues.

Note: once it started working the Seed Function started working as well