entity-framework

问题 I want to run tests with Effort and to do that I need to specify a connectionstring that also contains a reference to .csdl, .ssdl , and .msl files. The (non-working) connectionstring looks like this now: <add name="SQLAzureConnection" connectionString= "metadata=res://*/Model.projectContext.csdl| res://*/Model.projectContext.ssdl|res://*/Model.projectContext.msl; provider=System.Data.SqlClient; provider connection string="Data Source=(LocalDb)\v11.0;Initial Catalog=Database_Nieuw;Integrated

问题 I want to run tests with Effort and to do that I need to specify a connectionstring that also contains a reference to .csdl, .ssdl , and .msl files. The (non-working) connectionstring looks like this now: <add name="SQLAzureConnection" connectionString= "metadata=res://*/Model.projectContext.csdl| res://*/Model.projectContext.ssdl|res://*/Model.projectContext.msl; provider=System.Data.SqlClient; provider connection string="Data Source=(LocalDb)\v11.0;Initial Catalog=Database_Nieuw;Integrated

问题 I often come across, in LINQ for Entity Framework, a pattern where I add a .Where clause if a string value is specified, like: IQueryable<Foo> query = Foos.AsQueryable() if (!string.IsNullOrWhitespace(nameFilter)) query = query.Where(x => x.Name == name); if (!string.IsNullOrWhitespace(addressFilter) != null) query = query.Where(x => x.Address == addressFilter ); if (!string.IsNullOrWhitespace(cityFilter) != null) query = query.Where(x => x.City == cityFilter ); // ... I wanted to clean this

问题 In a .NET Core 2.1 project, I'm using EF Core with Command pattern (using MediatR library) on a SQL Server database. I setup the project to avoid client query evaluation, by using these settings: var phaseOptions = new DbContextOptionsBuilder<PhaseDbContext>().UseSqlServer(configuration.GetConnectionString("PhaseDbContext"), sqlServerOptions => sqlServerOptions .EnableRetryOnFailure( maxRetryCount: 5, maxRetryDelay: TimeSpan.FromSeconds(30), errorNumbersToAdd: null)) .ConfigureWarnings

问题 I'm developing a DataBase First EF application and everything is working great with the auto-generated code and app.config sections. But when I try to remove the connection string of the app.config and put it as parameter on the DbContext constructor I cannot get it to work. The connection string in the app.config: <add name="EntityContext" connectionString="metadata=res://*/ModelHistory.csdl|res://*/ModelHistory.ssdl|res://*/ModelHistory.msl;provider=Oracle.ManagedDataAccess.Client;provider

问题 Entity Framework Core Throwing error while doing update-database Error:- Introducing FOREIGN KEY constraint 'FK_UserRoleRelationship_UserRoels_ParentUserRoleId' on table 'UserRoleRelationship' may cause cycles or multiple cascade paths. Specify ON DELETE NO ACTION or ON UPDATE NO ACTION, or modify other FOREIGN KEY constraints. Could not create constraint or index. public class UserRoleRelationship { [Key] public int Id { get; set; } [Required] public Guid UserRoleRelationshipId { get; set; }

问题 Entity Framework Core Throwing error while doing update-database Error:- Introducing FOREIGN KEY constraint 'FK_UserRoleRelationship_UserRoels_ParentUserRoleId' on table 'UserRoleRelationship' may cause cycles or multiple cascade paths. Specify ON DELETE NO ACTION or ON UPDATE NO ACTION, or modify other FOREIGN KEY constraints. Could not create constraint or index. public class UserRoleRelationship { [Key] public int Id { get; set; } [Required] public Guid UserRoleRelationshipId { get; set; }

问题 Entity Framework Core Throwing error while doing update-database Error:- Introducing FOREIGN KEY constraint 'FK_UserRoleRelationship_UserRoels_ParentUserRoleId' on table 'UserRoleRelationship' may cause cycles or multiple cascade paths. Specify ON DELETE NO ACTION or ON UPDATE NO ACTION, or modify other FOREIGN KEY constraints. Could not create constraint or index. public class UserRoleRelationship { [Key] public int Id { get; set; } [Required] public Guid UserRoleRelationshipId { get; set; }

问题 Entity Framework Core Throwing error while doing update-database Error:- Introducing FOREIGN KEY constraint 'FK_UserRoleRelationship_UserRoels_ParentUserRoleId' on table 'UserRoleRelationship' may cause cycles or multiple cascade paths. Specify ON DELETE NO ACTION or ON UPDATE NO ACTION, or modify other FOREIGN KEY constraints. Could not create constraint or index. public class UserRoleRelationship { [Key] public int Id { get; set; } [Required] public Guid UserRoleRelationshipId { get; set; }

问题 I have ConsoleApplication on .NET Core and also i added my DbContext to dependencies, but howewer i have an error: Unable to create an object of type 'MyContext'. For the different patterns supported at design time, see https://go.microsoft.com/fwlink/?linkid=851728 i've added: var context = host.Services.GetRequiredService<MyContext>(); Also i've added private readonly DbContextOptions<MyContext> _opts; in my Post Class: using (MyContext db = new MyContext(_opts)) { db.Posts.Add(postData);