I am using Code first approach for oracle with Entity framework 5.0.0.0.
i am getting below error during migration
No MigrationSqlGenerator found for provider 'Oracle.ManagedDataAccess.Client'. Use the SetSqlGenerator method in the target migrations configuration class to register additional SQL generators.
i have added Oracle.ManagedDataAccess, Version=4.121.1.0 in solution and able to execute
Enable-Migrations and add-migration Initial in package manage console but when i am going to excute update-database command then getting above error message and database and table is not created in oracle 11g.please let me know what should be do.it's correct dll or we need to add additional changes.
Related
This is an EF Core, ASP.NET Core 3 Preview 5 project in VS 2019. All is working for
PM>Add-Migration Initial
PM>Update-Database
The SQL Server db created correctly based on MyDbContext and Startup.cs and appsettings.json connection string. (so everything is in place)
However if I change MyDbContext either adding a new DbSet or adding a property to an existing entity and run Update-Database nothing happens. No error message.
What I've tried so far:
Completely clean the project either in VS 2019 either by manually in file system
Exit VS, start VS
Deleting the migration folder in the project and DROP the database in SQL Server and starting from ground zero
The idea behind Migrations is to update the database schema and keep it in sync with your application data models (entities), so that you do not need to drop the database and re-create it again (which would cause data loss).
So whenever you do any changes to the Models/DbContext you need to Add-Migration, then do Update-Database.
For more information about migrations read this.
In a new code-first asp.net-core project connecting to my SQL-server database. When I run
add-migration MyInitialMigration
a migration file is created, then executed in SQL server creating the database, table structure with fields, indexes, etc. and populating the tables with the seed data from my DBInitialiser. The table __MigrationHistory is not created in the database and the ModelSnapshot.cs file is created. At this point I haven't run
update-database
which from everything I can find, I should need to run before the database, seed data, etc. is actually created. As far as I can tell, I've not got automatic migrations enabled.
Because of this, subsequent migrations aren't applied to the database because the tables already exist, which I'm guessing it figures out by looking for the __MigrationHistory table and not finding any rows in it.
How can I either get the initial add-migration to add the __MigrationHistory table or how do I get the migration to only happen when I enter update-database?
Not sure if it's related, but another project that was migrating fine last week now doesn't work properly. The migration .cs file is created fine, but when it automatically tries to create the database, etc. (when previously I needed to run update-database ) I get the error
Invalid JSON primitive: "C:\\x\\Migrations\\20171108125832_MyInitialMigration.cs",
"metadataFile": "C:\\x\\Migrations\\20171108125832_MyInitialMigration.Designer.cs",
"snapshotFile": "C:\\x\\Migrations\\MyContextModelSnapshot.cs"
}.
which relates to the following command I the migrations .cs file
migrationBuilder.CreateIndex(
name: "IX_tablea_tableID2",
table: "tablea",
column: "tableID2");
which as far as I can tell is identical to the several blocks of code above it which all work fine. I've tried deleting the migration files and database and rerunning the add-migration with the same effect. Each time I delete everything and start again like this, a different index causes the error message, even if it worked the previous time.
Has there been an update which breaks/alters how migrations work that I've missed?
You must have something odd in your code, like calling dbContext.Database.EnsureCreatedAsync(). This will create tables and database, but no migrations.
In previous versions of ASP.NET Core / EF Core (1.x), the Configure method of Startup class would not be executed, when running the EF Core tools (either add-migration in Powershell or dotnet ef migrations add in command line).
In order for the __MigrationHistory Table to be created, the migration must be applied with either dbContext.Database.MigrateAsync() or by database-update/dotnet ef database update.
However, with the new versions the migrations (or the dbContext.Database.EnsureCreated()) will be applied on every EF Core tools command.
The new pattern for performing DbContext discovery is to have a BuildWebHost static file, which configures the whole application and have extension methods in Main(...) method to perform the migration and seeding.
My previous answer on the new way to apply migrations (and seeding) covers the code.
The ASP.NET Core Annoucement documents this changes (its always a good idea to subscribe to this GitHub repository to receive notifications about new features and breaking changes)
I have an asp.net core mvc website using entity framework core.
I don't know how it initially happened, but I can't get past the error:
"There is already an object named AspNetRoles in the database"
I ended up deleted the database, deleting all my migration .cs files and starting from scratch.
I've then tried
add-migration MyInitialMigration
same error
I then deleted the database again, and tried a direct
update-database
(without adding a migration)
still the same error
I tried changing the appsettings config string to point to a new, non-existing database.
Still the same error!
Previously on MVC5/EF6 I've encountered this error and have resolved it using the same method as this answer:
There is already an object named in the database
-Add-Migration Initial -IgnoreChanges
However -IgnoreChanges is unsupported in EFCore
Or previously on EF6 I've resolved it by adding a migration, then deleting everything in the Up/Down and running an empty migration. This has not worked on EFCore
How can I continue? I've checked the migration table and they're always empty even though it's created the whole database each time. Just doesn't seemed to have logged it in the migrations table
Found my issue.
I had followed this tutorial to load appsettings from EntityFramework:
https://docs.asp.net/en/latest/fundamentals/configuration.html#example-entity-framework-settings
In the EntityFrameworkConfigurationProvider there is a public override void Load() which has a dbContext.Database.EnsureCreated(); and a CreateAndSaveDefaultValues
Between the two of those it looks like it was initializing the database without tracking the migration.
I commented those out, ran a migration and it worked fine. Hopefully I don't have to comment them out every time I want to run a migration :/
This error happened after I changed my database (I stopped using MSSQLLocalDB and started using Sql Server from the production table).
Here is what I did to make it work :
Deleting the migrations folder
Commenting the last changes I wanted to apply
Calling the Add-Migration command : Add-Migration InitialDbChange
Commenting all the commands inside the Up method of the migration file created (keeping only the content of the Down method)
Calling the update-database command : update-database
I have a now a clean Migration from my database. Now my futur changes will be from this baseline.
Found the solution from this link : https://cmatskas.com/ef-core-migrations-with-existing-database-schema-and-data/
I've just had the same issue, and seems like Database.EnsureCreated() doesn't use migrations, you can use Database.Migrate() instead which is what I've just tried and seems to work, but time will tell when I try another migration.
If you're like me and you pull a copy of your production database to work on in development, make sure all of the migrations in your Migration folder are listed in the __EFMigrationsHistory table of your database. If you move the schema to the production database after your development is complete, you're probably not moving the migrations from that table over to your production database. If any of the migrations in your project are missing from that table, EF will try to update the database with any of the missing migrations. In my case, none of the migrations were listed in the database table, so it started by trying to add the initial migration. After adding all of the migrations to the table (except the latest one that I wanted to update the database), EF updated the database correctly.
I recently setup a dev site and am using IdentityServer3 with IdentityManager, both from thinktecture, and IdentityManager is designed to create the database for itself, but can be configured to work with an existing db. I was able to get IdentityManager into a local db I had previously created with the default schema, but I would like to switch it to a new schema. Basically the question is that I can't figure out how to set the desired schema in the db in IdentityManager and can anyone in here give any insight?
There are many ways to do this (idsrv3 is very configurable). A common way is to add the MembershipReboot package, subclassing the MembershipReboot factory classes, and then loading your new factories during the idsrv3 startup. You will also need the IdentityServer3.MembershipReboot project, which acts as a go-between between IdentityServer3 and MembershipReboot.
In the visual studio package manager console you add the projects like so:
Install-Package BrockAllen.MembershipReboot
Install-Package IdentityServer3.MembershipReboot
You can use the idsrv3 samples as an example of how to set up your classes. https://github.com/IdentityServer/IdentityServer3.Samples
That will give you the data entities you need. Then to write your entities to a database, add the MembershipReboot.EF project and set up a database connection string that gets passed to your override of the MembershipRebootDbContext() class.
Install-Package BrockAllen.MembershipReboot.Ef
The first time you start your identity server, MembershipReboot.EF will use Entity Framework to automatically create your database schema and start writing your entities there.
Hope that gets you started, sorry if it's not what you're asking!
I am developing windows phone app. I am using Linq to Sql with WCF application. I have drag and drop the tables and store procedure in Model.dbml. I am stuck with following error.
Error 1 Build failed due to validation errors in E:\path\Model.dbml. Open the file and resolve the issues in the Error List, then try rebuilding the project.
I am not getting about this error. How can I solve this error?
.dbml is related to Linq to Sql Classes. It's not relevant to ADO.NET or Windows Phone and for sure it's fully supported in WCF and often the recommanded approach.
Linq to Sql uses a database-first approach where you have the database and model your classes after the DB schema. It's a completely client side thing : a set of information about your tables in the database and how you're going to map them to .NET objects. The DBML file is mapping that defines your classes based on your database schema.
DBML Validation is a specific task in the Build process.
To see the error, open the dbml file (desginer) and check Error List Tab. It's a compilation error and not a runtime exception.
Frist clean your project and next build it.
I had this problem.