code-first

问题 I used code first for create and update database. My update-database commands in package manager worked until yesterday. But today it is not working and has this error: CREATE DATABASE permission denied in database 'master'. I do not any changes on connection string and other config. So I try to Update-database to another project on my system and my windows and I can recreate and update this database without any problem. Can you help me for fix this error? This is my connection string for

问题 I have a database that I created for a site using Entity Framework 4.1 code first. I need to add a simple property to one of my entity classes, and add a corresponding (possibly nullable) column to the database without losing any of the data in the database. I think I can take down the site, alter the database to add the column, and redeploy website with an updated entity class, but I'm not sure that's the best way to do this schema upgrade. Is there a standard (or just better) way of doing a

问题 I use entity framework core 2 Code first to generate data in Oracle 11g, the entity provider is dotConnect, my POCO class is as follow: public partial class Favoritepage { [Key] [DatabaseGenerated(DatabaseGeneratedOption.Identity)] public int Id { get; set; } public int Personnelid { get; set; } public int Pageid { get; set; } } My DbContext is as follow: public partial class ModelContext : DbContext { public virtual DbSet<Favoritepage> Favoritepage { get; set; } protected override void

问题 I have two tables with composite primary keys: public class Event { [Key] [Column(Order = 1)] public string ID1 { get; set; } [Key] [Column(Order = 2)] public int ID2 { get; set; } public DateTime EventDate { get; set; } public string DocID1 { get; set; } public int DocID2 { get; set; } } public class EventDocument { [Key] [Column(Order = 1)] public string ID1 { get; set; } [Key] [Column(Order = 2)] public int ID2 { get; set; } public string Name { get; set; } public string SurName { get; set

问题 I have two entities, User and UserPermission. The User entity contains all your normal fields, Id, Username, Email, etc and the UserPermission entity has two values, UserId and PermissionId. I have written a repository method GetUserWithPermissions that originally utilized the Include extension and did something like this: return dbContext.Users.Include(u => u.UserPermission).Where(u => u.Username.Equals(username)).FirstOrDefault(); It works great but the issues is that there are going to be

问题 I have a application using code first; in search section I have to gather information from 3 tables and their related tables so I made a view; and since there is no syntax for code first to create view (I think so; please let me know if I'm wrong) I used pure SQL script; on model creating to prevent EF to create a table with same name as table (VIEW_SEARCH) I did : protected override void OnModelCreating(DbModelBuilder modelBuilder) { modelBuilder.Ignore<View_Search>(); } any ways application

问题 I have the following [DataContractAttribute] public class Animal { [Key] [XmlElement(ElementName = "Id")] [DataMember()] public Guid Id { get; set; } [XmlElement(ElementName = "AnimalType")] [DataMember()] public List<AnimalType> AnimalType { get; set; } } And i map it through the code first approach with EF to tables modelBuilder.Entity<Animal>().ToTable("Animal"); As you see I have not performed some complex mapping, but the List of AnimalType enumerations did not get mapped automatically

问题 With Entity Framework and Code First, is it possible to let it create and use a table with no primary keys? I can't get this setup to work: public class Report { public virtual int ReportId public virtual ICollection<ReportChanges> ReportChanges } public class ReportChanges { public virtual Report Report public virtual string EditorName public virtual DateTime Changed } Note that I've excluded assigning a primary key in ReportChanges. But with this setup I get: " Unable to infer a key for

问题 I am working with Entity Framework Code First, and am trying to create a class that will map to a View. I know how to do it for a table, like below: [Table("FIL002")] public class FIL002 { [Key] [DatabaseGeneratedAttribute(DatabaseGeneratedOption.None)] public Int64 Payer_Number { get; set; } public string Payer_Name { get; set; } } However, I could not find an attribute for View (Like [Table(...)] . Is there one? 回答1: Views are queried in the exact same way as tables. Therefore, just use

问题 I'm evaluating EF4 and have a pretty basic question...I think, that I can't seem to find an answer for.. take the following example: public class Question { public string question {get;set;} public string answer {get; set;} } public class Person { public string Id {get; set;} public string Name {get; set;} public List<Question> Questions {get; set;} } Then I have the following tables in the database Person ( id, name ) Question ( id, personId, question, answer, ) Can I use the EF4 code first