My Database Team created a database called XMEN.
I need to use that specific database with my project. I have full admin rights on that database but not on the server (they won't give it to me).
CREATE DATABASE permission denied in database 'master'.
When I run my project, I get the error above because I don't have permission to create a database. How can I use entity frameworks to specify which database to use? I want Entity Framework to manage everything else (tables, relationships, etc)
------------- UPDATED 9/17/2020 - 9:12 AM EST
public class XmenContext : DbContext
{
//public XmenContext(DbContextOptions<XmenContext> options)
// : base(options)
//{
//}
public XmenContext() : base("XmenDatabase")
{
}
Now I get an error saying cannot convert from String to Microsoft.EntityFrameworkCore.DbContextOptions
I clicked the link in your answer.
You should add the database name to the connection string in your configuration file.
If you need some help you can view here :
https://learn.microsoft.com/en-us/ef/ef6/fundamentals/configuring/connection-strings
If you are having trouble add your connection string to the question (without sensitive information) and I will try to help.
Good luck !
I am using Entity Framework model-first. After finishing my site, I did a Publish. I am using Entity Framework and a database connection setup using a connection string from settings.config:
<add key="thenna"
value="server=11.3.34.45;database=montage;user id=sample;password=Test;trusted_connection=false;"/>
I have config changed server database details.
My entity framework connection string in web.config:
<add name="tickandtieEntities"
connectionString="metadata=res://*/Entityframework.Tickmarks.csdl|res://*/Entityframework.Tickmarks.ssdl|res://*/Entityframework.Tickmarks.msl;provider=System.Data.SqlClient;provider connection string="data source=DESKTOP-QD6A981\SQLEXPRESS;initial catalog=tickandtie;user id=sa;password=tickmarks;MultipleActiveResultSets=True;App=EntityFramework""
providerName="System.Data.EntityClient" />
When I change web.config file with server details I get an error
Cannot open database "tickandtie" requested by the login
How can I configure Entity Framework in web.config when I move my app to the host server? Please help me anyone
You can do this by setting the connection string on your EF Db Context at creation time, passing your setting value to your EF context.
E.g.: adding a constructor on your context, which uses the base DbContext constructor to pass the connection string:
public class MyDbContext : DbContext
{
public MyDbContext(string connString) : base(connString)
{
}
}
Which then make your context used like:
var connectionString = "" // Get the value of of your custom config file here.
var ctx = new MyDbContext(connectionString);
As stated above, you need to read your connection string value first out of your settings.config file.
I'm migrating to Entity Framework v6 and I'm struggling to build code that will let me define my SQL 2008R2 database connection in the code. I cannot store the connection string information within the app.config file due to this library being a dll that multiple applications will be using. The idea is to maintain all the Database connections within 1 dll without having to reference the entity-libraries in the front-ends nor specify a connection string.
With EF5 I was able to use a partial class and define the connection string in the DBContext, that method does not seem to work with EF6. I'd like an example of an EF6 SQL database connection entirely defined within code. Most of the examples of EF6 out there are for code-first models, I already have the database tables, I just need to build the interface.
-Hiram
(assuming that you are using the EF Designer)
You can't just pass a connection string to the DbContext when using the code generated from the EF6 Designer because the DbContext needs the information created from the EDMX. But you can still create a partial class that has a constructor that accepts a connection string. You will just have to create an ObjectContext and pass that to the DbContext constructor.
Here is an example:
using System.Data.Entity.Core.EntityClient;
using System.Data.Entity.Core.Metadata.Edm;
using System.Data.Entity.Core.Objects;
using System.Data.SqlClient;
namespace Northwind.Model {
public partial class NorthwindEntities {
public NorthwindEntities(string connectionString)
: base(GetObjectContext(connectionString), true) {
}
private static ObjectContext GetObjectContext(string connectionString) {
// You can use the metadata portion of the connection string the the designer added to your config for the paths
var paths = new[] {
"res://*/Northwind.csdl",
"res://*/Northwind.ssdl",
"res://*/Northwind.msl"
};
var workspace = new MetadataWorkspace(paths, new[] { typeof(NorthwindEntities).Assembly });
var connection = new EntityConnection(workspace, new SqlConnection(connectionString));
return new ObjectContext(connection);
}
}
}
You can still define the connection string in the DBContext in EF6.
public class ApplicationDbContext : DbContext
{
public ApplicationDbContext()
: base(#"Your connection string here") { }
// Rest of your DbContext code
}
But hard coding a connection string in there isn't very versatile. Even though your DbContext will be in it's own dll, it can still read the app.config or web.config of your primary project if it is in the same solution (and I'm fairly sure it will work even if you add your DbContext dll as a reference).
Just add a reference to System.Configuration in your DbContext project, and then you can get at the connection string with either ConfigurationManager.ConnectionStrings["MyConnectionStringName"].ConnectionString or ConfigurationManager.AppSettings["MyConnectionStringName"]
And you would store the connection string in your primary applications web.config in the <connectionStrings> section OR in the 'app.config' in the <appSettings> section
Note that if you do it this way (by reading from web.config or app.config), you should change your DbContext code accordingly:
public class ApplicationDbContext : DbContext
{
public ApplicationDbContext()
: base("MyConnectionStringName") { }
// Rest of your DbContext code
}
I am getting into the Entity Framework, but I am unsure if I am missing a critical point in the code-first approach.
I am using a generic repository pattern based on the code from https://genericunitofworkandrepositories.codeplex.com/ and have created my entities.
But when I try to access or modify the entity I run into the following:
System.InvalidOperationException: The entity type Estate is not part
of the model for the current context.
It happens when I am trying to access it from my repository:
public virtual void Insert(TEntity entity)
{
((IObjectState)entity).ObjectState = ObjectState.Added;
_dbSet.Attach(entity); // <-- The error occurs here
_context.SyncObjectState(entity);
}
The database (./SQLEXPRESS) is created just fine, but the entities (tables) is just not created on startup.
I am wondering if I need to explicit set the mapping of the entities? Is EF not able to this by its own?
My Entity is:
public class Estate : EntityBase
{
public int EstateId { get; set; }
public string Name { get; set; }
}
My context is as so:
public partial class DimensionWebDbContext : DbContextBase // DbContextBase inherits DbContext
{
public DimensionWebDbContext() :
base("DimensionWebContext")
{
Database.SetInitializer<DimensionWebDbContext>(new CreateDatabaseIfNotExists<DimensionWebDbContext>());
Configuration.ProxyCreationEnabled = false;
}
public new IDbSet<T> Set<T>() where T : class
{
return base.Set<T>();
}
}
Is there any specific reason why this error occurs? I have tried enable migrations and enable automatic migrations without any help either.
Put this in your custom DbContext class:
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
modelBuilder.Entity<Estate>().ToTable("Estate");
}
If your tables are not created on startup, this is why. You need to tell the DbContext about them in the OnModelCreating method override.
You can either do custom per-entity mappings here, or separate them out into separate EntityTypeConfiguration<T> classes.
Apparently, this error is very generic, it could have a number of reasons. In my case, it was the following: The connection string (in Web.config) generated by the .edmx was invalid. After almost a day of trying everything, I changed the connection string from the EF string to an ADO.NET string. This solved my issue.
For example, the EF string looks something like this:
<connectionStrings>
<add name="BlogContext"
connectionString="metadata=res://*/BloggingModel.csdl|
res://*/BloggingModel.ssdl|
res://*/BloggingModel.msl;
provider=System.Data.SqlClient
provider connection string=
"data source=(localdb)\v11.0;
initial catalog=Blogging;
integrated security=True;
multipleactiveresultsets=True;""
providerName="System.Data.EntityClient" />
</connectionStrings>
And the ADO.NET string looks like this:
<connectionStrings>
<add name="BlogContext"
providerName="System.Data.SqlClient"
connectionString="Server=.\SQLEXPRESS;Database=Blogging;
Integrated Security=True;"/>
</connectionStrings>
Source: http://msdn.microsoft.com/nl-nl/data/jj556606.aspx
For me the issue was that I had not included the Entity Class within my db set inside the context for entity framework.
public DbSet<ModelName> ModelName { get; set; }
You may try removing the table from the model and adding it again. You can do this visually by opening the .edmx file from the Solution Explorer.
Steps:
Double click the .edmx file from the Solution Explorer
Right click on the table head you want to remove and select "Delete from Model"
Now again right click on the work area and select "Update Model from Database.."
Add the table again from the table list
Clean and build the solution
The problem may be in the connection string. Ensure your connection string is for SqlClient provider, with no metadata stuff related to EntityFramework.
My issue was resolved by updating the metadata part of the connection string. Apparently it was pointing at the wrong .csdl / .ssdl / .msl reference.
I've seen this error when an existing table in the database doesn't appropriately map to a code first model. Specifically I had a char(1) in the database table and a char in C#. Changing the model to a string resolved the problem.
One other thing to check with your connection string - the model name. I was using two entity models, DB first. In the config I copied the entity connection for one, renamed it, and changed the connection string part. What I didn't change was the model name, so while the entity model generated correctly, when the context was initiated EF was looking in the wrong model for the entities.
Looks obvious written down, but there are four hours I won't get back.
For me the issue was that I used the connection string generated by ADO.Net Model (.edmx). Changing the connection string solved my issue.
This can also occur if you are using a persisted model cache which is out of date for one reason or another. If your context has been cached to an EDMX file on a file system (via DbConfiguration.SetModelStore) then OnModelCreating will never be called as the cached version will be used. As a result if an entity is missing from your cached store then you will get the above error even though the connection string is correct, the table exists in the database and the entity is set up correctly in your DbContext.
The message was pretty clear but I didn't get it at first...
I'm working with two Entity Framework DB contexts sysContext and shardContext in the same method.
The entity I had modified\updated is from one context but then I tried to save it to the other context like this:
invite.uid = user.uid;
sysContext.Entry(invite).State = EntityState.Modified;
sysContext.SaveChanges(); // Got the exception here
but the correct version should be this:
invite.uid = user.uid;
shardContext.Entry(invite).State = EntityState.Modified;
shardContext.SaveChanges();
After passing the entity to the correct context this error went away.
I was facing the same issue with EntityFrameworkCore trying to update a range of values.
This approach did not work
_dbSet.AttachRange(entity);
_context.Entry(entity).State = EntityState.Modified;
await _context.SaveChangesAsync().ConfigureAwait(false);
After adding UpdateRange method and removing attach and entry everything work
_dbSet.UpdateRange(entity);
await _context.SaveChangesAsync().ConfigureAwait(false);
Sounds obvious, but make sure that you are not explicitly ignoring the type:
modelBuilder.Ignore<MyType>();
map of the entity (even an empty one) added to the configuration will lead to having the entity type be part of the context. We had an entity with no relationship to other entities that was fixed with an empty map.
if you are trying DB first then be sure that your table has primary key
Visual Studio 2019 seems to cause this for me. I fixed it by generating the edmx model again in 2017.
For me it was caused because I renamed the entity class.When I rolled it back it was Ok.
I had this
using (var context = new ATImporterContext(DBConnection))
{
if (GetID(entity).Equals(0))
{
context.Set<T>().Add(entity);
}
else
{
int val = GetID(entity);
var entry = GetEntryAsync(context, GetID(entity)).ConfigureAwait(false);
context.Entry(entry).CurrentValues.SetValues(entity);
}
await context.SaveChangesAsync().ConfigureAwait(false);
}
This was in an async method, but I've forgot to put await before GetEntryAsync, and so I got this same error...
Make sure you have set up your mapping class to point to your SQL table
I've had the same problem and in my case, the reason why I got this error message was that the property identifiers in my class file did not match the identifiers defined in the database, e.g. I wrote an identifier with a beginning uppercase letter while in the database it was all lowercase.
I've faced this issue after publishing my project using web deploy. It happened because my the metadata in connection string of my publish profile was not same as connection string in my project because I dropped the edmx for some reason and added it back with different Name. To fix it I had to delete the publish profile and redeploy again so that the metadata matches the names.
With models created from database (First Database), it is not possible to replace the connection string (with metadata and providerName="System.Data.EntityClient", from EDMX) by one of SQL.
The only possibility I have found is to create another context that uses the SQL connection (providerName="System.Data.SqlClient")
<connectionStrings>
<add name="DefaultConnection" providerName="System.Data.SqlClient" connectionString="Max Pool Size=10000;Pooling=true;Data Source=MyIpServer;Initial Catalog=myDatabase;Persist Security Info=True;User ID=MyUser;Password=MyPassword;TrustServerCertificate=False" />
<add name="Entities" providerName="System.Data.EntityClient" connectionString="metadata=res://*/Datos.MyModel.csdl|res://*/Datos.MyModel.ssdl|res://*/Datos.MyModel.msl;provider=System.Data.SqlClient;provider connection string="Max Pool Size=10000;Pooling=true;data source=MyIpServer;initial catalog=myDatabase;persist security info=True;user id=MyUser;password=MyPassword;trustservercertificate=False;MultipleActiveResultSets=True;App=EntityFramework"" />
</connectionStrings>
With the two context options, with Identity:
public partial class ContextWithUsers : IdentityDbContext<MyUser>
{
public ContextWithUsers() : base("name=DefaultConnection")
{
}
}
public class MyUser : IdentityUser
{
// aditional table user data
//public virtual MyUserInfo MyUserInfo { get; set; }
}
Normal context:
public partial class ContextWithoutUsers : DbContext
{
public ContextWithoutUsers () : base("name=Entities")
{
}
}
This solution works, but... Why is it not possible to use the same context with the First Database model + Identity ?
NOTE 1: if you force change connection string show:
System.Data.Entity.Infrastructure.UnintentionalCodeFirstException: 'The context is being used in Code First mode with code that was generated from an EDMX file for either Database First or Model First development. This will not work correctly. To fix this problem do not remove the line of code that throws this exception. If you wish to use Database First or Model First, then make sure that the Entity Framework connection string is included in the app.config or web.config of the start-up project. If you are creating your own DbConnection, then make sure that it is an EntityConnection and not some other type of DbConnection, and that you pass it to one of the base DbContext constructors that take a DbConnection. To learn more about Code First, Database First, and Model First see the Entity Framework documentation here: http://go.microsoft.com/fwlink/?LinkId=394715'
NOTE 2: External Class library with EDMX + Data and ASP.NET webform project
Delete the .edmx file and add it again. Especially, if you have upgraded the Entity Framework.
Could be stupid, but if you only got this error on some Table, dont forget to clean your project and rebuild (could save a lot of time)
I am looking at using MVC5 to compliment an existing ASP.Net application (that is not MVC).
The app has been configured using database first.
I need to change the database connection string at runtime depending on who is logged in. (This is easy to do in the current app through data adapters).
There are over 1000 existing databases and more can created at runtime - so Web.config is not an option. Schema is common to all databases.
So far, I have managed to switch the database on the Controller - but this means changing substantially the generated code - there must be an easier way! - Help!
Added comment:
The model is a SaaS accounting application. Each database stores all ledgers for a client company and has approximately 125 tables within it. They are kept separate for security and also portability (some accountants even require to download the SQL data in it's entirety for their clients).
Example code:
The site is built on the Contoso University model:
http://www.asp.net/mvc/tutorials/mvc-5/database-first-development/setting-up-database
It works in its basic form, but I need the connection changed for each clients data:
So looking at the Sales ledger - under the Sales controller we have:
public class SalesController : Controller
{
private Sales db = new Sales();
.....
The Sales definition is:
public partial class Sales : DbContext
{
public Sales()
: base("name=Sales")
{
}
The "name=Sales" links to the WebConfig and gives it the starting database.
Looking at the : base definition takes me to System.Data.Entity.DbContext which is a locked file!
I have trawled through various sites and tried putting the connection string in the Sales class the following being one of the suggestions:
public Sales(string connString) : base (connString)
but this throws:
Code generated using the T4 templates for Database First and Model First development may not work correctly if used in Code First mode. To continue using Database First or Model First ensure that the Entity Framework connection string is specified in the config file of executing application. To use these classes, that were from Database First or Model First, with Code First add any additional configuration using attributes or the DbModelBuilder API and then remove the code that throws this exception
Line 32: protected override void OnModelCreating(DbModelBuilder modelBuilder)
Line 33: {
Line 34: throw new UnintentionalCodeFirstException();
Line 35: }
Line 36:
That's where I am stuck - even if I use the same connection string as in the WebConfig!!
(It mentions Code First mode - which it wasn't?)
You could have your data access layer access an interface providing the connection string it uses? In the same way, if using EF, it might be a context rather than a connection string
public interface class IClient
{
string ConnectionString {get;set;}
}
public class DataAccess
{
private IClient _connectionString;
public DataAccess(IClient client)
{
_connectionString = client.ConnectionString;
}
}
This of course would change slightly based on your design. I would probably have the authentication for all clients on the same db, then based on who authenticates a factory could return an IClient which could then be used by DAL, Repository or whatever you have. IClient would not really just have a connection string or context, you could have other properties or methods on there too, relevant to requirements.
Internally, the Repository (for example) might use that context or connection string in the constructor, so it establishes the correct connection. Methods would not change.
Add a new parameterised Constructor as explained below.
In "Connectionstring" pass your connection like:
string Connectionstring="Data Source=;Initial Catalog=abc;Persist Security Info=True;
User ID=dsds;Password=dsdsd;MultipleActiveResultSets=True";
public Sales()
: base("name=Sales")
{
}
public Sales(string Connectionstring)
: base(Connectionstring)
{
}