ef-core-2.0

来源： https://stackoverflow.com/questions/49721742/ef-code-first-not-creating-the-database

问题 I have a new .NET Core Web API project that has the following projects structure: API -> Business / Domain -> Infrastructure The API is very thin with only the API methods. The Business / Domain layer has all my business logic. And finally, my Infrastructure layer has my DB classes using EF Core 2.0. I know using .NET Core built-in Dependency Injection I can add a reference from the API project to the Infrastructure project, then add the following code in the StartUp.cs file: services

问题 I have a new .NET Core Web API project that has the following projects structure: API -> Business / Domain -> Infrastructure The API is very thin with only the API methods. The Business / Domain layer has all my business logic. And finally, my Infrastructure layer has my DB classes using EF Core 2.0. I know using .NET Core built-in Dependency Injection I can add a reference from the API project to the Infrastructure project, then add the following code in the StartUp.cs file: services

问题 I have a new .NET Core Web API project that has the following projects structure: API -> Business / Domain -> Infrastructure The API is very thin with only the API methods. The Business / Domain layer has all my business logic. And finally, my Infrastructure layer has my DB classes using EF Core 2.0. I know using .NET Core built-in Dependency Injection I can add a reference from the API project to the Infrastructure project, then add the following code in the StartUp.cs file: services

问题 I have the following code var dbContext = Setup.ConfigureDBContext(); var wo = await dbContext.WorkOrders.Where(x => x.WorkOrderID == 88).SingleOrDefaultAsync(); var t = wo.Confidence; wo.ModifiedDateTime = DateTime.UtcNow; wo.Confidence = t; await dbContext.SaveChangesAsync(); in the above query i am assigning the same Confidence but changing the ModifiedDateTime EF generates the following SQL exec sp_executesql N'SET NOCOUNT ON; UPDATE [WorkOrders] SET [ModifiedDateTime] = @p0 WHERE

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 This is the method in my generic repository: public async Task<TEntity> GetByCondition(Expression<Func<TEntity, bool>> predicate, Func<DbSet<TEntity>, IQueryable<TEntity>> baseQuery = null) { IQueryable<TEntity> q = _context.Set<TEntity>(); if (baseQuery != null) { q = baseQuery(_context.Set<TEntity>()); } return await q.Where(predicate).FirstOrDefaultAsync(); } This is the usage in my business logic: Expression<Func<Countries, bool>> whereExpr = x => x.SlugHebrew == slug || x.SlugEnglish ==