I have the following one-to-many database structure generated by code first. Many Buttons can be added with a relation back to a single GSMUnit. BtnNo should be unique (for every GSMUnitId), and shouldn't be duplicated. Currently it is possible to duplicate. how can i prevent this?
public class GSMUnit
{
public int Id { get; set; }
[MaxLength(20)]
public string Model { get; set; }
[MaxLength(40)]
public string GsmName { get; set; }
[MaxLength(40)]
public string TelephoneNum { get; set; }
public int GSMSiteId { get; set; }
public virtual GSMSite GSMSite { get; set; }
public virtual GSMSetting GSMSettings { get; set; }
public virtual ICollection<Button> Buttons { get; set; }
}
public class Button
{
public int Id { get; set; }
[MaxLength(30)]
public string Primary { get; set; }
[MaxLength(30)]
public string Divert1 { get; set; }
[MaxLength(30)]
public string Divert2 { get; set; }
[MaxLength(30)]
public string Divert3 { get; set; }
[MaxLength(20)]
public string AptNo { get; set; }
[MaxLength(10)]
public string Code { get; set; }
[MaxLength(4)]
public string DTO { get; set; }
[MaxLength(4)]
public string Timeband { get; set; }
[MaxLength(15)]
public string BtnNo { get; set; }
[MaxLength(20)]
public string AptName { get; set; }
public int GSMUnitId { get; set; }
public virtual GSMUnit GSMUnit { get; set; }
}
You can use the Index attribute for that:
public class Button
{
public int Id { get; set; }
[MaxLength(30)]
public string Primary { get; set; }
[MaxLength(30)]
public string Divert1 { get; set; }
[MaxLength(30)]
public string Divert2 { get; set; }
[MaxLength(30)]
public string Divert3 { get; set; }
[MaxLength(20)]
public string AptNo { get; set; }
[MaxLength(10)]
public string Code { get; set; }
[MaxLength(4)]
public string DTO { get; set; }
[MaxLength(4)]
public string Timeband { get; set; }
[MaxLength(15)]
public string BtnNo { get; set; }
[MaxLength(20)]
public string AptName { get; set; }
[Index(IsUnique = true)]
public int GSMUnitId { get; set; }
public virtual GSMUnit GSMUnit { get; set; }
}
But I recommend you to take a look on Fluent API. It's easier to configure in my opinion.
Related
I am using Entity Framework. I have tried everything, searching and adding keys but Ienter image description here cannot understand what the problem is and how to resolve it.
public class Reservation
{
[Key]
public int BookingID { get; set; }
public int CustomerID { get; set; }
public int RoomID { get; set; }
public string BookingDate { get; set; }
public int Check_In { get; set; }
public int Check_Out { get; set; }
public int Adults { get; set; }
public int Children { get; set; }
public int NoOfNights { get; set; }
[ForeignKey("RoomID")]
public virtual Room Rooms { get; set; }
[ForeignKey("CustomerID")]
public virtual CustomerDetails CustomerDetail { get; set; }
public virtual ICollection<Payment> Payment { get; set; }
}
public class CustomerDetails
{
[Key]
public int CustomerID { get; set; }
public string FirstName { get; set; }
public string LastName { get; set; }
public int PostCode { get; set; }
public string State { get; set; }
public int PhoneNumber { get; set; }
public string Email { get; set; }
public string Password { get; set; }
public virtual ICollection<Reservation> Reservations { get; set; }
}
enter image description here
All tables need a primary key or you can't use Entity Framework.
Can someone please help me with this problem? I am new to EF and i don't know what happen to this code:
Please find below query in the Controller:
foreach (var i in tt)
{
db.tbl_transaction.Add(i);
db.tbl_transactionlist.Add(tm.tlist);
var tools = (from j in db.tbl_tools_and_equips where j.itemno == i.controlno select j).First();
//tools.location = i.destinationid;
//tools.linemodel = i.line_model;
//tools.usage = i.process_assign;
tools.status = i.status;
tools.date_maintain = i.date_maintain;
tools.date_next_maintain = i.date_next_maintain;
}
try
{
/*return error: invalid columns in db.SaveChanges*/
db.SaveChanges();
For my Model:
public partial class tbl_transaction
{
public int transferevent { get; set; }
public string transactionno { get; set; }
public Nullable<int> itemno { get; set; }
public string assetdesc { get; set; }
public string serialno { get; set; }
public string barcode { get; set; }
public string sourcelocationid { get; set; }
public string destinationid { get; set; }
public Nullable<System.DateTime> transactiondate { get; set; }
public Nullable<int> quantity { get; set; }
public string unitmeasure { get; set; }
public string remarks { get; set; }
public string #ref { get; set; }
public string actg_rem { get; set; }
public string label { get; set; }
public string station { get; set; }
public string line_model { get; set; }
public string process_assign { get; set; }
public string status { get; set; }
public string controlno { get; set; }
public string category { get; set; }
public Nullable<System.DateTime> date_maintain { get; set; }
public Nullable<System.DateTime> date_repair { get; set; }
public string defect { get; set; }
public string repair_made { get; set; }
public Nullable<System.DateTime> date_next_maintain { get; set; }
}
Every time I execute the query, it always return invalid column name. Your help is very much appreciated.
public class Category
{
[Key]
public int CategoryId { get; set; }
public int ParentCategoryId { get; set; }
public string Name { get; set; }
public string Description { get; set; }
public int Status { get; set; }
public virtual ICollection<Category> ParentCategories { get; set; }
public virtual ICollection<ImageSet> ImageSets { get; set; }
[ForeignKey("ParentCategoryId")]
public virtual Category ParentCategory { get; set; }
}
public class ImageSet
{
[Key]
public int ImageSetId { get; set; }
public int CategoryId { get; set; }
public string Name { get; set; }
public string Description { get; set; }
public string InsertDate { get; set; }
public int Status { get; set; }
public virtual ICollection<Image> Images { get; set; }
[ForeignKey("CategoryId")]
public virtual Category Category { get; set; }
}
public class Image
{
[Key]
public int ImageId { get; set; }
public int ImageSetId { get; set; }
public string Name { get; set; }
public string Description { get; set; }
public string ImageUrl { get; set; }
public string ThumbImageUrl { get; set; }
public string InsertDate { get; set; }
public int Status { get; set; }
[ForeignKey("ImageSetId")]
public virtual ImageSet ImageSet { get; set; }
}
Context:
public DbSet<Category> Categories { get; set; }
public DbSet<Image> Images { get; set; }
public DbSet<ImageSet> ImageSets { get; set; }
error page:Introducing FOREIGN KEY constraint 'FK_dbo.ImageSets_dbo.Categories_CategoryId' on table 'ImageSets' 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. See previous errors.
Whats the problem?
You need to add this:
modelBuilder.Entity<ImageSet>()
.HasRequired(is => is.Category)
.WithMany(c => c.ImageSets)
.WillCascadeOnDelete(false);
Here are good explanations of why this is happening :
https://stackoverflow.com/a/19390016/1845408
https://stackoverflow.com/a/17127512/1845408
I am getting warning errors of no key having been defined for each of my class library classes despite the fact that I have the [Key] tag and including the System.ComponentModel.DataAnnotations namespace, here is my context:
Context:
namespace Project.Data
{
public class ProjectContext : DbContext, IProjectContext
{
public ProjectContext(string connString)
: base(connString)
{
this.Configuration.LazyLoadingEnabled = true;
Database.SetInitializer<ProjectContext>(new ProjectInitializer());
this.Database.CreateIfNotExists();
this.Database.Initialize(true);
}
public IDbSet<Article> Article { get; set; }
public IDbSet<Brand> Brand { get; set; }
public IDbSet<Colour> Colour { get; set; }
public IDbSet<Customer> Customer { get; set; }
public IDbSet<CustomerCredit> CustomerCredit { get; set; }
public IDbSet<Delivery> Delivery { get; set; }
public IDbSet<DesignerTicket> DesignerTicket { get; set; }
public IDbSet<EuroRate> EuroRate { get; set; }
public IDbSet<Gift> Gift { get; set; }
public IDbSet<GZero> GZero { get; set; }
public IDbSet<InvoiceStock> InvoiceStock { get; set; }
public IDbSet<PrintOptions> PrintOptions { get; set; }
public IDbSet<Product> Product { get; set; }
public IDbSet<ProductLocation> ProductLocation { get; set; }
public IDbSet<Sale> Sale { get; set; }
public IDbSet<SaleAccount> SaleAccount { get; set; }
public IDbSet<SalesToWeb> SalesToWeb { get; set; }
public IDbSet<Shop> Shop { get; set; }
public IDbSet<Staff> Staff { get; set; }
public IDbSet<Ticket> Ticket { get; set; }
public IDbSet<Transfer> Transfer { get; set; }
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
modelBuilder.Conventions.Remove<PluralizingTableNameConvention>();
}
}
}
Context Interface:
namespace Project.Data
{
public interface IProjectContext
{
IDbSet<Article> Article { get; set; }
IDbSet<Brand> Brand { get; set; }
IDbSet<Colour> Colour { get; set; }
IDbSet<Customer> Customer { get; set; }
IDbSet<CustomerCredit> CustomerCredit { get; set; }
IDbSet<Delivery> Delivery { get; set; }
IDbSet<DesignerTicket> DesignerTicket { get; set; }
IDbSet<EuroRate> EuroRate { get; set; }
IDbSet<Gift> Gift { get; set; }
IDbSet<GZero> GZero { get; set; }
IDbSet<InvoiceStock> InvoiceStock { get; set; }
IDbSet<PrintOptions> PrintOptions { get; set; }
IDbSet<Product> Product { get; set; }
IDbSet<ProductLocation> ProductLocation { get; set; }
IDbSet<Sale> Sale { get; set; }
IDbSet<SaleAccount> SaleAccount { get; set; }
IDbSet<SalesToWeb> SalesToWeb { get; set; }
IDbSet<Shop> Shop { get; set; }
IDbSet<Staff> Staff { get; set; }
IDbSet<Ticket> Ticket { get; set; }
IDbSet<Transfer> Transfer { get; set; }
}
}
[Key] decorated class example:
namespace Project.Data
{
public class Article
{
[Key]
public int ArticleID;
public bool IsCore;
public string Make;
public string Product;
public decimal Sale;
public string Department;
public string Scale;
public string Detail;
public DateTime InDate;
public decimal Reduce;
public bool IsOnSale;
public string VAT;
public bool IsOnWeb;
public string ProductCode;
public string Pick;
public string MemoDetail;
public string LOC;
public string ColourCode;
public bool StatusFlag;
public string Terminal;
}
}
Despite have the [Key] placed on Article I am getting the following message for the article class as shown below and this is repeated for each of the classes:
Project.Data.Article: : EntityType 'Article' has no key defined. Define the key for this EntityType.
Anyone see what I am doing wrong here? would be greatly appreciated
Define the members of your class as public properties as opposed to public variables like you have here, by including {get; set;} at the end of the declaration
I have 2 classes, course and student, and I want to get student courses with student id
help me please
I'm using entity framework code first
public class Course {
public int CourseID { get; set; }
public string Title { get; set; }
public string Details { get; set; }
public string img { get; set; }
public DateTime DateAdded { get; set; }
public Guid UserAddID { get; set; }
public Guid userEditID { get; set; }
public int SubCategoryID { get; set; }
public string Code { get; set; }
public string Summury { get; set; }
public decimal Price { get; set; }
public bool IsGift { get; set; }
public DateTime DateUpdated { get; set; }
public bool DelFlag { get; set; }
public DateTime? DelDate { get; set; }
public Guid? UserDelID { get; set; }
public ICollection<Student> Students { get; set; }
}
public class Student {
[Key]
public int StudentID { get; set; }
public string Name { get; set; }
public DateTime? DateBirth { get; set; }
public int? Age { get; set; }
public int? Sex { get; set; }
public string Email { get; set; }
public string Phone { get; set; }
public string Mobile { get; set; }
public string Mobile2 { get; set; }
public string UniversityID { get; set; }
public string CollegeID { get; set; }
public string IdentityID { get; set; }
public string Address { get; set; }
public string Education { get; set; }
public decimal? Payments { get; set; }
public string HowToKnow { get; set; }
public DateTime? GradeDate { get; set; }
public string LaterCourses { get; set; }
public string Job { get; set; }
public string Specialist { get; set; }
public string Notes { get; set; }
public int StatueID { get; set; }
public Guid? UserID { get; set; }
public DateTime? DateAdded { get; set; }
public Guid UserAddID { get; set; }
public Guid userEditID { get; set; }
public DateTime DateUpdated { get; set; }
public bool DelFlag { get; set; }
public DateTime? DelDate { get; set; }
public Guid? UserDelID { get; set; }
public virtual IList<Course> Courses { get; set; }
}
I want to get all courses for a given StudentID using a lambda expression.
var students = repository.Query<Course>(c => c.Student.Any(st=>st.StudentID == StudentID)