code-first

问题 I have two tables: Requirement ID (int) PK ClientID (int) JobNumber (int) Comment ID (int) PK Job_ID (int) Comment (varchar) The tables don't have foreign keys and there's no possibility of adding any. I'm trying to map them in EF. I have classes for each and I'm trying to define the relationship in fluent code to map the Comment.Job_ID to the Requirement.JobNumber. A requirement can have many comments. Requirement has a list of Comments and Comment has a Requirement property. I have this

问题 I am following this article on MSDN. I ported it to EF Code First. public interface IUnitOfWork { IRepository<Employee> Employees { get; } IRepository<TimeCard> TimeCards { get; } void Commit(); } public class HrContext : DbContext { public DbSet<Employee> Employees { get; set; } public DbSet<TimeCard> TimeCards { get; set; } protected override void OnModelCreating(ModelBuilder modelBuilder) { modelBuilder.Entity<Employee>() .HasMany(e => e.TimeCards) .WithOptional(tc => tc.Employee); } }

问题 I'm trying to update an object that I have previously saved with EntityFramework 4.1 (CodeFirst) The class Job has the following properties ... public class Job { [key] public int Id { get; set; } public string Title { get; set; } public Project Project { get; set; } public JobType JobType { get; set; } public string Description { get; set; } } The initial create works fine, but the update only commits changes to the strings.. If I change the child objects eg the JobType Property from

问题 I'm overriding SaveChanges on my DbContext in order to implement an audit log. Working with many-to-many relationships or independent associations is relatively easy as EF creates ObjectStateEntries for any changes to those kinds of relationships. I am using foreign key associations, and when a relationship between entities changes all you get is an ObjectStateEnty that says for example entity "Title" has "PublisherID" property changed. To a human this is obviously a foreign key in Title

问题 I'm overriding SaveChanges on my DbContext in order to implement an audit log. Working with many-to-many relationships or independent associations is relatively easy as EF creates ObjectStateEntries for any changes to those kinds of relationships. I am using foreign key associations, and when a relationship between entities changes all you get is an ObjectStateEnty that says for example entity "Title" has "PublisherID" property changed. To a human this is obviously a foreign key in Title

问题 I'm learning Entity Framework (currently using EF6 beta) and I'm using the code first pattern on an existing database. The entities and DbContext class are created automatically using a T4 template. I would like to prevent the DbContext from creating / altering anything into the database at runtime. How can I do that? 回答1: When you do enable-migrations command, you will be presented with folder /Migrations under which you can find file named Configuration.cs . Within constructor of that file,

问题 We have our own external convention of naming objects and I need to change the naming convention for the auto generated foreign key constraints. Now it looks like: FK_dbo.City_dbo.CityType_City_CityTypeId but I would like it to be called City_FKC_CityType . I found a similar question which says that you can change the name of constraints manually. However, this does not suit me, since I have a lot of tables and foreign key constraints. I found some information about "Custom Code First

问题 I am working with a system that has many stored procedures that need to be displayed. Creating entities for each of my objects is not practical. Is it possible and how would I return a DataTable using ExecuteStoreQuery ? public ObjectResult<DataTable> MethodName(string fileSetName) { using (var dataContext = new DataContext(_connectionString)) { var returnDataTable = ((IObjectContextAdapter)dataContext).ObjectContext.ExecuteStoreQuery<DataTable>("SP_NAME","SP_PARAM"); return returnDataTable;

问题 I'm creating a POCO model to use with entity framework code first CTP5. I'm using the decoration to make a property map to a PK column. But how can I define a PK on more then one column, and specifically, how can I control order of the columns in the index? Is it a result of the order of properties in the class? Thanks! 回答1: You can specify the column order in the attributes, for instance: public class MyEntity { [Key, Column(Order=0)] public int MyFirstKeyProperty { get; set; } [Key, Column

问题 I have just created a database and done my first migration (just a simple table add). Now I want to add some stored procedures which I have just added by writing the sql and executing it in Management Studio. But I would like to include these stored procedures if possible in a migration so that they are saved and I can run an Up or Down method against them. Is this possible and if so what syntax needs to be used? Or will I just have to add/edit/remove them using Management Studio? 回答1: I've