In my web.config, I have a connection string set which is different in my web.release.config where it is changed to use our production database using an xdt:transform. The problem is, I have only been running add-migration and update-database on the database contained within web.config. Is there some way I can run update-database when I publish using the release configuration?
To get around this in the short term, I change the connection string contained within web.config to the one contained in web.release.config and then run update-database prior to publishing, but this defeats the purpose of using an xdt:transform?
If you're using the VS Publish Web tool, you can check "Execute Code First Migrations (runs on application start)" in Settings.
If you're deploying to Azure, they can also run migrations on their side, I believe (I remember reading about "new" Azure-specific things regarding this just a couple of months ago, definitely less than a year).
Otherwise, you can always pass arguments to Update-Database to target another database (ConnectionStringName, ConnectionString, ConnectionProviderName), you shouldn't have to fiddle with the Web.config file.
Related
I have been having trouble working with migrations and an Azure Sql Database for the past couple of weeks.
I run enable-migrations and a migrations folder with a congfiguration file is created.
I then run Add-Migration InitialCreate and a migration is created with empty Up() and Down() methods.
PM> Enable-Migrations
Checking if the context targets an existing database...
Code First Migrations enabled for project MyService.
PM> Add-Migration InitialCreate
Scaffolding migration 'InitialCreate'.
The Designer Code for this migration file includes a snapshot of your
current Code First model. This snapshot is used to calculate the changes to
your model when you scaffold the next migration. If you make additional
changes to your model that you want to include in this migration, then you
can re-scaffold it by running 'Add-Migration InitialCreate' again.
I deleted an old database from my App Service and created a new one. This is now being targeted in my Web.config:
<add name="MS_TableConnectionString" connectionString="Data Source=(localdb)\MSSQLLocalDB;AttachDbFilename=|DataDirectory|\aspnet-MyService-20180212689875.mdf;Initial Catalog=aspnet-MyService-20180212578997;Integrated Security=True;MultipleActiveResultSets=True"
providerName="System.Data.SqlClient" />
I have a feeling my code is targeting the old database which has been deleted on azure but holds the tables for the objects I'm now trying to add.
Update:
Removed the data objects and created a migration and it has been populated with the Delete code for non-existent tables(which existed in my last database). Definitely an issue with pointing to the right place. Any ideas?
Pretty new to Azure so not sure where to look to try and fix this.
Any help appreciated!
After adding migration, remember to enter "update-database" in Package Manager Console, which command runs the Up method to create the database and then it runs the Seed method to populate the database.
I have a feeling my code is targeting the old database which has been deleted on azure but holds the tables for the objects I'm now trying to add.
According to the code you provided, you set the database in Local in web.config and delete the database on Azure, but you could populate data to the deleted database on azure. There is no possible to achieve it.
Actually, when you publish you Web App to Azure, you could pick on the "Excute Code First Migrations" in Visual Studio and check if the TestContext is the database connection that you use now.
Each time you get both of them and after migrations, you will populate the data to the latest the database on Azure. You could read this article to know the details about Code First Migrations and Deployment.
We're using EF 6, in database-first mode.
We've been building a database migration package, using FluentMigrator, and we've been running our migrations against empty LocalDb databases in our solution, for use in integration testing, etc.
Because we need our solutions to build wherever they're checked out, we've been using |DataDirectory| in the connection strings.
We've written some unit [sic] tests, running against LocalDb instances, running the migrations first to ensure that the tests are running against the current schema. (Yes, these are integration tests, but we're using a unit test framework, and I don't want to argue about it.)
What I would like to do next is to change our configuration so that when we run "Update Model from Database" on our .edmx files, it's the LocalDb instance that the tool looks to. And I can't make that work.
My guess is that whatever tool is running, when we do this, doesn't have it's DataDirectory set where I need it to be, in it's appdomain.
Does anyone know what tool this might be? And how I can configure it to connect to a localdb instance, that's using |DataDirectory| to create a relative path?
Before anyone marks this as a duplicate, none of the questions similar to this addressed any of my concerns or answered any of my questions.
I am currently developing all the POCOs and data contexts in a library project, and running migrations from within this project. The database I'm updating is the development database.
What do I do if I want to create the current schema to a fresh, new database? I figure that all I have to do is to change the connection string in web.config and run Update-Database, correct?
While the live/production database is up and running, I want to add new columns and new tables to the schema, and test it out in development. So I switch back the connection string to the development database's connection string, and run Update-Database.
Going back and forth between two databases seems like I'll get conflicts between _MigrationHistory tables and the auto-generated migration scripts.
Is it safe to manually delete the _MigrationHistory tables in both databases, and/or delete the migration files in /Migrations (so I'll run Add-Migration again)? How do we manage this?
What do I do if I want to create the current schema to a fresh, new database?
- Yes, to create fresh database to the current migration level you simply modify the connection string to point to a database that does not yet exist and run update-database. It will run all the migrations in order.
As far as migrating to the Production database, I am running the update-database command with the -script switch to acquire the raw sql and then applying that script to the production database manually. This is helpful if you need to keep a record of sql commands run against the database as well. Additionally, you can generate the script explicitly from a specific migration to another specific migration via some of the other update-database switches.
Alternatively, you can create an Idempotent script that works from any migration by using the–SourceMigration $InitialDatabase switch and optionally specify an end migration with –TargetMigration
If you delete the _MigrationHistory tables you will have issues where the generated script will be trying to add columns that already exist and such.
You may find the following link helpful:
Microsoft Entity Framework Migrations
I would suggest having a separate trunk in your source code repository - one pointing to production and one to development to avoid risks of switching between the two in visual studio.
Me also had the same problem, even when using one and the same database - due to some merges in the repository, and the mix of automatic/manual migrations. For some reason the EF was not taking into account the target database, and calculating what scripts need to me executed, based on what is already in the database.
To fix this, I go to the [__MigrationHistory] table on the target database and get the latest migration name. This will help EF to determinate the state of the DB, and will execute just the scripts needed.
then the following script is run:
update-database -script -sourcemigration {latest migration name}
This creates update script that is specific to the target database (the connection string should be correct, as discussed in the other comments)
you can also use -force parameter if needed
this way you can update any database to latest version, no mater in what version you found it, if it has MigrationHistory table.
Hope this helps
My production and my developmental database went out of synch and it gave me endless problems. I solved it using a tool from Red-Gate to match up the databases. After using the tool, the databases were exactly the same but my migration was not working and I started to get odd errors i.e. trying to add tables/ columns that already existed etc. I solved that. I just deleted the migration folder on the local, recreated it, added the initial migration, updated the database and then matched the data of this migration file (local) to the one on the host (delete all the data in the migration file on the host, and add the same data that is on the local into the host). A more detailed explanation is at:
migration synch developmental and production databases
I'm trying to get Entity framework migrations working. I've enabled code first migrations, its created a migrations folder, config file and the mig history table, but no initial create. Am i missing a step? This is a new db created by EF (4.3.1).
This behavior is not in place by default, but it is available to you easily in many different forms.
You can call context.Database.CreateIfNotExists(); at application startup.
You can use one of the built-in DatabaseInitializers. The CreateDatabaseIfNotExists initializer is built into EntityFramework and just needs to be added to your project.
You could create your own custom database initializer which includes option #1 inside of itself. Example: Code First Migrations and initialization
You can include DatabaseInitializers in your project either by code or via a config file.
Include an EntityFramework Database Initializer via code:
In your application startup you can setup the DatabaseInitializer like so:
System.Data.Entity.Database.SetInitializer<DairyMmmContext>(new System.Data.Entity.CreateDatabaseIfNotExists<DairyMmmContext>());
NOTE: this code has changed multiple times throughout the life of entityframework! This example is for EF 4.3 which is the current production release available via nuget.
Include an EntityFramework Database Initializer via configuration element:
<configuration>
<entityFramework>
<contexts>
<context type="MyNamespace.MyEFDataContext, AssemblyName">
<databaseInitializer
type="System.Data.Entity.CreateDatabaseIfNotExists`2[[MyNamespace.MyEFDataContext, AssemblyName],
[MyNamespace.Migrations.Configuration, AssemblyName]], EntityFramework" />
</context>
</contexts>
</entityFramework>
</configuration>
You'll notice this can be a little "ungraceful" with this configuration. You need to replace AssemblyName above with the name of the assembly you keep your entityframework stuff in, replace MyNamespace.MyEFDataContext with the fully qualified name of your entityframework data context, and replace MyNamespace.Migrations.Configuration with the fully qualified name to your configuration class (by default in the Migration folder inside your project).
EDIT: Edited to respond to additional comments
A migration is a change from one schema definition to another schema definition. Creating the empty database is not a migration (but everything after that is). There will be no migration source file in your project for just creating an empty db, that is done in code by the initializer.
If you are already using the DropCreateDatabaseAlways initializer it should be doing that. However, I noticed you are setting the initializer in code which means there is the opportunity for a timing problem (setting the initializer after your context is already past the point of calling any initializers).
You can force entityframework to run your initializer at any point in code with context.Database.Initialize(true); (The parameter is a true/false to force the initialization regardless of the current state). That would drop and recreate your database every time.
But you can also just make sure your initializer is setup as early as possible in your application's life cycle (before you have created a single instance of your context).
"Initial Create" is NOT created automatically! You need to create that yourself. Some tutorials of EF are confusing and I had the same misunderstanding as you.
What you need to do:
-Add-Migration InitialModel
If you already have created your database tables and domain model, then:
-Add-Migration InitialModel -IgnoreChanges
From this point, your code will be in sync with database. Anytime you change the code, you can use Add-Migration to add the changes to your database.
The article / tutorial here here (on microsoft.com)
describes the reason that an initialCreate migration doesn't exist. The migration will only be added if the Database already exists. Otherwise, the first migration will be the 'initialCreate' as there is no point in creating a migration to a Database that doesn't exist yet... no DB means there is nothing to roll back to, on a down migration.
Here is the pertinent paragraph:
Run the Enable-Migrations command in Package Manager Console
This command has added a Migrations folder to our project, this new folder contains two files:
The Configuration class. This class allows you to configure how Migrations behaves for your context. For this walkthrough we will just use the default configuration.
Because there is just a single Code First context in your project, Enable-Migrations has automatically filled in the context type this configuration applies to.
An InitialCreate migration. This migration was generated because we already had Code First create a database for us, before we enabled migrations. The code in this scaffolded migration represents the objects that have already been created in the database. In our case that is the Blog table with a BlogId and Name columns. The filename includes a timestamp to help with ordering.
If the database had not already been created this InitialCreate migration would not have been added to the project. Instead, the first time we call Add-Migration the code to create these tables would be scaffolded to a new migration.
Not sure it's the same but I had a similar issue. I think my problem was related to the fact that I dont use a connections string from the config file to get my connection string.
Fiddling with the start up project in the solution and also the projet combo in the Package Manager Console I was able to generate that first migration.
Also make shure you have a connections string with the name of your dbContext class so the Package Manager can find it.
I am using EF 6 RC1 and ran into this problem where neither the InitialCreate nor __MigrationHistory were being created when running Enable-Migrations.
Actually, just after upgrading from EF 5 to EF 6 I ran Enable-Migrations and for some reason it created a __MigrationHistory table using the EF 5 schema, so I deleted it and my Migrations directory and tried to start over.
But every time I deleted the Migrations directory it wouldn't create an InitialCreate or __MigrationHistory. I tried dropping and recreating the database and restarting Visual Studio 2012 to no avail. I gave up for the day and the next morning tried again - after letting my computer sit for about 8 hours it then created the InitialCreate. I am guessing there must be a cache somewhere that has a really long timeout - anyone? I am also guessing that rebooting might clear the cache, but I didn't try that.
Whatever the case, it is possible to use PM> Add-Migration InitialCreate to do that step manually.
Anyway, I still didn't get a __MigrationHistory table. Apparently, EF 6 has changed from creating it during the Enable-Migrations command to instead only creating it during the Update-Database command. And since my schema had already been created at that point, I needed to tear it down and recreate it manually:
PM> Update-Database -TargetMigration:0
PM> Update-Database
I also stopped after the first command to check the state of the database to ensure I was updating the correct one, since according to this, the database connection string is picked up or autogenerated depending on the configuration, and unless it is configured right, there is no guarantee you are going to access the database or instance of SQL Server you intend to.
After running both commands it created a __MigrationHistory table - and it didn't create it as a system table (which I didn't really want anyway), so all is good. Not exactly the same problem as the OP, but hopefully this will be helpful to someone else.
References:
http://elegantcode.com/2012/04/12/entity-framework-migrations-tips/
Reset Entity-Framework Migrations
How to recreate migrations from scratch
I know this is old, but there is no accepted answer and I had same issue.
The trick is Enable-Migrations command. As stated here there is a command Enable-Migrations –EnableAutomaticMigrations. What it does it starts migrations exactly where you are.
If you want the first migration to be creation of database, just run Enable-Migrations (without --EnableAutomaticMigrations).
And remember to set initializer:
Database.SetInitializer(new MigrateDatabaseToLatestVersion<LicenseContext, Configuration>());
It looks like CodeFirst stops doing its homework when it doesn't have full control of the database (I suppose).
The scenario is a web site hosted on Arvixe.com (or I suppose any other shared hosting server), where I have to create databases only from their control panel (and NOT with Sql Server Management Studio, just to say...).
Once created an empty database, I register a connection in the web site, and I use it to generate database from poco objects like in:
add-migration m1 -targetdatabase myconnection
This generates correctly my FIRST migration, that I can apply without problems with
update-database -targetdatabase myconnection
The first concern, not too important, is that since the database is existing, it will NOT issue the Seed command, so I have to insert my first records by hand, but this is not a great problem.
Then I change my poco objects, and I need to update the database, but when I issue ANOTHER
add-migration m2 -targetdatabase myconnection
it gives the error:
System.Data.Entity.Migrations.MigrationsPendingException: Unable to generate an explicit migration because the following explicit migrations are pending: [201111081426466_m1]. Apply the pending explicit migrations before attempting to generate a new explicit migration.
This is really strange, since if I look at the database, I can see even the table __MigrationHistory, but then it looks like it cannot recognize it...
Anyone with the same problem, or some good tip to where investigate?
Thanks in advance,
Andrea Bioli
I had this problem. I was able to resolve it by providing a connectionString and a connectionProviderName parameter to both the Update-Database and the Add-Migration commands.
If you have many projects in your solution with multiple config files, Package Manager seems to be confused. In my case, I had one project selected as the default project for Package Manager Console, but it was pulling the connection string from the Visual Studio solution default start-up project instead.