How do I enable EF migrations for multiple contexts to separate databases

Question

How do I enable Entity Framework 5  version 5 0 0  migrations for multiple DB contexts in the same project  where each context corresponds to its own database  When I run Enable-Migrations in the PM console  Visual Studio 2012   there s an error because of there being multiple contexts   PM gt  Enable-Migrations More than one context type was found in the assembly  DatabaseService   To enable migrations for DatabaseService Models Product1DbContext  use Enable-Migrations -ContextTypeName DatabaseService Models Product1DbContext  To enable migrations for DatabaseService Models Product2DbContext  use Enable-Migrations -ContextTypeName DatabaseService Models Product2DbContext    If I run Enable-Migrations -ContextTypeName DatabaseService Models Product1DbContext I m not allowed to run Enable-Migrations -ContextTypeName DatabaseService Models Product2DbContext because a migration already exists  Migrations have already been enabled in project  DatabaseService   To overwrite the existing migrations configuration  use the -Force parameter

User · Answer

To update database type following codes in PowerShell     Update-Database -context EnrollmentAppContext    if more than one databases exist only use this codes otherwise not necessary

User · Answer

The 2nd call to Enable-Migrations is failing because the Configuration cs file already exists   If you rename that class and file  you should be able to run that 2nd Enable-Migrations  which will create another Configuration cs   You will then need to specify which configuration you want to use when updating the databases   Update-Database -ConfigurationTypeName MyRenamedConfiguration

User · Answer

In addition to what  ckal suggested  it is critical to give each renamed Configuration cs its own namespace   If you do not  EF will attempt to apply migrations to the wrong context   Here are the specific steps that work well for me   If Migrations are messed up and you want to create a new  baseline     Delete any existing  cs files in the Migrations folder In SSMS  delete the   MigrationHistory system table    Creating the initial migration    In Package Manager Console   Enable-Migrations -EnableAutomaticMigrations -ContextTypeName NamespaceOfContext ContextA -ProjectName ProjectContextIsInIfNotMainOne -StartupProjectName NameOfMainProject  -ConnectionStringName ContextA  In Solution Explorer  Rename Migrations Configuration cs to Migrations ConfigurationA cs   This should automatically rename the constructor if using Visual Studio   Make sure it does  Edit ConfigurationA cs  Change the namespace to NamespaceOfContext Migrations MigrationsA Enable-Migrations -EnableAutomaticMigrations -ContextTypeName NamespaceOfContext ContextB -ProjectName ProjectContextIsInIfNotMainOne -StartupProjectName NameOfMainProject  -ConnectionStringName ContextB  In Solution Explorer  Rename Migrations Configuration cs to Migrations ConfigurationB cs   Again  make sure the constructor is also renamed appropriately  Edit ConfigurationB cs  Change the namespace to NamespaceOfContext Migrations MigrationsB add-migration InitialBSchema -IgnoreChanges -ConfigurationTypeName ConfigurationB -ProjectName ProjectContextIsInIfNotMainOne -StartupProjectName NameOfMainProject  -ConnectionStringName ContextB   Update-Database -ConfigurationTypeName ConfigurationB -ProjectName ProjectContextIsInIfNotMainOne -StartupProjectName NameOfMainProject -ConnectionStringName ContextB  add-migration InitialSurveySchema -IgnoreChanges -ConfigurationTypeName ConfigurationA -ProjectName ProjectContextIsInIfNotMainOne -StartupProjectName NameOfMainProject  -ConnectionStringName ContextA   Update-Database -ConfigurationTypeName ConfigurationA -ProjectName ProjectContextIsInIfNotMainOne -StartupProjectName NameOfMainProject -ConnectionStringName ContextA    Steps to create migration scripts in Package Manager Console    Run command  Add-Migration MYMIGRATION -ConfigurationTypeName ConfigurationA -ProjectName ProjectContextIsInIfNotMainOne -StartupProjectName NameOfMainProject -ConnectionStringName ContextA   or -  Add-Migration MYMIGRATION -ConfigurationTypeName ConfigurationB -ProjectName ProjectContextIsInIfNotMainOne -StartupProjectName NameOfMainProject -ConnectionStringName ContextB   It is OK to re-run this command until changes are applied to the DB  Either run the scripts against the desired local database  or run Update-Database without -Script to apply locally   Update-Database -ConfigurationTypeName ConfigurationA -ProjectName ProjectContextIsInIfNotMainOne -StartupProjectName NameOfMainProject -ConnectionStringName ContextA   or -  Update-Database -ConfigurationTypeName ConfigurationB -ProjectName ProjectContextIsInIfNotMainOne -StartupProjectName NameOfMainProject -ConnectionStringName ContextB

User · Answer

EF 4 7 actually gives a hint when you run Enable-migrations at multiple context   More than one context type was found in the assembly  Service Domain    To enable migrations for  Service Domain DatabaseContext Context1    use Enable-Migrations -ContextTypeName Service Domain DatabaseContext Context1  To enable migrations for  Service Domain DatabaseContext Context2   use Enable-Migrations -ContextTypeName Service Domain DatabaseContext Context2

User · Answer

In case you already have a  Configuration  with many migrations and want to keep this as is  you can always create a new  Configuration  class  give it another name  like   class MyNewContextConfiguration   DbMigrationsConfiguration lt MyNewDbContext gt               then just issue the command   Add-Migration -ConfigurationTypeName MyNewContextConfiguration InitialMigrationName   and EF will scaffold the migration without problems  Finally update your database  from now on  EF will complain if you don t tell him which configuration you want to update   Update-Database -ConfigurationTypeName MyNewContextConfiguration    Done   You don t need to deal with Enable-Migrations as it will complain  Configuration  already exists  and renaming your existing Configuration class will bring issues to the migration history   You can target different databases  or the same one  all configurations will share the   MigrationHistory table nicely

User · Answer

If more databases exist use following codes in PowerShell  Add-Migration Starter -context EnrollmentAppContext      Starter  is Migration Name   EnrollmentAppContext  is name of my app Context    You can open PowerShell in VS by doing  Tools- gt NuGet Package Manager- gt Package Manager Console

User · Answer

I just bumped into the same problem and I used the following solution  all from Package Manager Console   PM gt  Enable-Migrations -MigrationsDirectory  Migrations ContextA  -ContextTypeName MyProject Models ContextA PM gt  Enable-Migrations -MigrationsDirectory  Migrations ContextB  -ContextTypeName MyProject Models ContextB   This will create 2 separate folders in the Migrations folder  Each will contain the generated Configuration cs file  Unfortunately you still have to rename those Configuration cs files otherwise there will be complaints about having two of them  I renamed my files to ConfigA cs and ConfigB cs  EDIT   courtesy Kevin McPheat  Remember when renaming the Configuration cs files  also rename the class names and constructors  EDIT  With this structure you can simply do   PM gt  Add-Migration -ConfigurationTypeName ConfigA PM gt  Add-Migration -ConfigurationTypeName ConfigB   Which will create the code files for the migration inside the folder next to the config files  this is nice to keep those files together   PM gt  Update-Database -ConfigurationTypeName ConfigA PM gt  Update-Database -ConfigurationTypeName ConfigB   And last but not least those two commands will apply the correct migrations to their corrseponding databases   EDIT 08 Feb  2016  I have done a little testing with EF7 version 7 0 0-rc1-16348   I could not get the -o --outputDir option to work  It kept on giving Microsoft Dnx Runtime Common Commandline CommandParsingException  Unrecognized command or argument  However it looks like the first time an migration is added it is added into the Migrations folder  and a subsequent migration for another context is automatically put into a subdolder of migrations   The original names ContextA seems to violate some naming conventions so I now use ContextAContext and ContextBContext  Using these names you could use the following commands   note that my dnx still works from the package manager console and I do not like to open a separate CMD window to do migrations   PM gt  dnx ef migrations add Initial -c  ContextAContext  PM gt  dnx ef migrations add Initial -c  ContextBContext    This will create a model snapshot and a initial migration in the Migrations folder for ContextAContext  It will create a folder named ContextB containing these files for ContextBContext  I manually added a ContextA folder and moved the migration files from ContextAContext into that folder  Then I renamed the namespace inside those files  snapshot file  initial migration and note that there is a third file under the initial migration file     designer cs   I had to add  ContextA to the namespace  and from there the framework handles it automatically again   Using the following commands would create a new migration for each context  PM gt   dnx ef migrations add Update1 -c  ContextAContext  PM gt   dnx ef migrations add Update1 -c  ContextBContext    and the generated files are put in the correct folders

[.net] How do I enable EF migrations for multiple contexts to separate databases?

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