I am trying to Seed some sample Data
public class Condition
{
public int Id { get; set; }
public string Name { get; set; }
}
public class Entity
{
public int Id { get; set; }
public string Name { get; set; }
public int ConditionId { get; set; }
public virtual Condition Condition { get; set; }
}
and in my Seed method..
protected override void Seed(AppContext context)
{
Condition condition1 = new Condition();
condition1.Name = "Cond1";
Entity.Entity newEntity1 = new Entity.Entity();
newEntity1.Name = "Test1";
newEntity1.Condition = condition1;
context.Entities.Add(newEntity1);
Condition condition2 = new Condition();
condition2.Name = "Cond2";
Entity.Entity newEntity2 = new Entity.Entity();
newEntity2.Name = "Test Entity 2";
newEntity2.Condition = condition2;
context.Entities.Add(newEntity2);
context.SaveChanges();
}
I am getting this Exception constraint failed FOREIGN KEY constraint failed, I couldn't figure out what wrong I am doing here.
I tried calling context.SaveChanges() after first insertion too and it went fine. but the error appreared only after second context.SaveChanges() only.
protected override void Seed(AppContext context)
{
Condition condition1 = new Condition();
condition1.Id=1;
condition1.Name = "Cond1";
Entity.Entity newEntity1 = new Entity.Entity();
newEntity1.Name = "Test1";
newEntity1.ConditionId=1
newEntity1.Condition = condition1;
context.Entities.Add(newEntity1);
Condition condition2 = new Condition();
condition2.Id=2
condition2.Name = "Cond2";
Entity.Entity newEntity2 = new Entity.Entity();
newEntity2.Name = "Test Entity 2";
newEntity2.ConditionId=2;
newEntity2.Condition = condition2;
context.Entities.Add(newEntity2);
context.SaveChanges();
}
Hope This works..
Related
I'm trying to get the Audit:NET EntityFramework.Core extension to write an AuditLog entry per changed property.
For this purpose I've overidden the EntityFrameworkDataProvider.InsertEvent with a custom DataProvider.
The problem is, using DbContextHelper.Core.CreateAuditEvent to create a new EntityFrameworkEvent returns null.
The reason seems to be, at this point in the code execution DbContextHelper.GetModifiedEntries determines all EF Entries have State.Unmodified, even if they are clearly included in the EventEntry changes.
I'm trying to circumvent CreateAuditEvent by manually creating the contents is impossible due to private/internal properties.
Maybe there is an alternative solution to this problem I'm not seeing, i'm open to all suggestions.
Audit entity class
public class AuditLog
{
public int Id { get; set; }
public string Description { get; set; }
public string OldValue { get; set; }
public string NewValue { get; set; }
public string PropertyName { get; set; }
public DateTime AuditDateTime { get; set; }
public Guid? AuditIssuerUserId { get; set; }
public string AuditAction { get; set; }
public string TableName { get; set; }
public int TablePK { get; set; }
}
Startup configuration
Audit.Core.Configuration.Setup()
.UseCustomProvider(new CustomEntityFrameworkDataProvider(x => x
.AuditEntityAction<AuditLog>((ev, ent, auditEntity) =>
{
auditEntity.AuditDateTime = DateTime.Now;
auditEntity.AuditAction = ent.Action;
foreach(var change in ent.Changes)
{
auditEntity.OldValue = change.OriginalValue.ToString();
auditEntity.NewValue = change.NewValue.ToString();
auditEntity.PropertyName = change.ColumnName;
}
}
Custom data provider class
public class CustomEntityFrameworkDataProvider : EntityFrameworkDataProvider
{
public override object InsertEvent(AuditEvent auditEvent)
{
var auditEventEf = auditEvent as AuditEventEntityFramework;
if (auditEventEf == null)
return null;
object result = null;
foreach (var entry in auditEventEf.EntityFrameworkEvent.Entries)
{
if (entry.Changes == null || entry.Changes.Count == 0)
continue;
foreach (var change in entry.Changes)
{
var contextHelper = new DbContextHelper();
var newEfEvent = contextHelper.CreateAuditEvent((IAuditDbContext)auditEventEf.EntityFrameworkEvent.GetDbContext());
if (newEfEvent == null)
continue;
newEfEvent.Entries = new List<EventEntry>() { entry };
entry.Changes = new List<EventEntryChange> { change };
auditEventEf.EntityFrameworkEvent = newEfEvent;
result = base.InsertEvent(auditEvent);
}
}
return result;
}
}
Check my answer here https://github.com/thepirat000/Audit.NET/issues/323#issuecomment-673007204
You don't need to call CreateAuditEvent() you should be able to iterate over the Changes list on the original event and call base.InsertEvent() for each change, like this:
public override object InsertEvent(AuditEvent auditEvent)
{
var auditEventEf = auditEvent as AuditEventEntityFramework;
if (auditEventEf == null)
return null;
object result = null;
foreach (var entry in auditEventEf.EntityFrameworkEvent.Entries)
{
if (entry.Changes == null || entry.Changes.Count == 0)
continue;
// Call base.InsertEvent for each change
var originalChanges = entry.Changes;
foreach (var change in originalChanges)
{
entry.Changes = new List<EventEntryChange>() { change };
result = base.InsertEvent(auditEvent);
}
entry.Changes = originalChanges;
}
return result;
}
Notes:
This could impact performance, since it will trigger an insert to the database for each column change.
If you plan to use async calls to DbContext.SaveChangesAsync, you should also implement the InsertEventAsync method on your CustomDataProvider
The Changes property is only available for Updates, so if you also want to audit Inserts and Deletes, you'll need to add the logic to get the column values from the ColumnValues property on the event
I am using ASP.NET Boilerplate template.
I want to update Details table, which contains more than one item. If an item exists, it must update, otherwise a new one must be added and all other entries relating to Master primary key in Details table must be deleted. But it is showing an error:
Cannot insert explicit value for identity column in table
'SemesterDetails' when IDENTITY_INSERT is set to OFF
This is the Master table:
public class StudentDegreeCore : Entity<int>
{
[StringLength(150)]
[Required(ErrorMessage = "Enter Degree College ")]
public string DegreeCollege { get; set; }
[Required()]
public string CollegeID { get; set; }
[StringLength(7, ErrorMessage = "The {0} must be at least {2} characters long.", MinimumLength = 7)]
[Required(ErrorMessage = "Enter 10th Pass Year")]
public string CommencementYear { get; set; }
public List<StudentSemesterCore> SemesterDetails { get; set; }
}
This is the Details table, represented by the StudentSemesterCore class:
public class StudentSemesterCore
{
[DatabaseGeneratedAttribute(DatabaseGeneratedOption.Identity)]
public int Id { get; set; }
[StringLength(150)]
[Required(ErrorMessage = "Enter Year/Semester")]
public string YearOrSemester { get; set; }
[Required()]
public virtual int StudentDegreeID { get; set; }
[ForeignKey("StudentDegreeID")]
public virtual StudentDegreeCore StudentDegreeCore { get; set; }
[StringLength(4, ErrorMessage = "The {0} must be at least {2} characters long.", MinimumLength = 4)]
[Required(ErrorMessage = "Enter Semester Status")]
public string Status { get; set; }
[DisplayName("% of Marks")]
[RegularExpression(#"\d+(\.\d{1,2})?", ErrorMessage = "Numbers With Two decimal Place Allowed")]
public decimal MarkPercentage { get; set; }
}
This is the Update code:
_studentdegreeRepository.Update(st);
CurrentUnitOfWork.SaveChanges();
It shows an error when SaveChanges is called. Actually, I want to update the details if the same value exists, otherwise add new one and all other data relating to the same StudentDegreeID must be removed.
StudentSemesterCore is not derived from Entity.
You don't need to put Id property in StudentSemesterCore. Remove it.
Add StudentDegreeCoreId to StudentSemesterCore as foreign key reference.
I tried this
public override async Task<StudentDegreeDto> Create(StudentDegreeCreateDto input)
{
//CheckCreatePermission();
StudentDegreeCore st = new StudentDegreeCore();
try
{
StudentDegreeCore core = new StudentDegreeCore()
{
Id = input.Id,
Address1 = input.Address1,
Address2 = input.Address2,
City = input.City,
CollegeID = input.CollegeID,
CommencementYear = input.CommencementYear,
CompletionYear = input.CompletionYear,
CurrentYear = input.CurrentYear,
DegreeCollege = input.DegreeCollege,
DegreeId = input.DegreeId,
OverallPercent = input.OverallPercent,
PinCode = input.PinCode,
PostBox = input.PostBox,
State = input.State,
StreamId = input.StreamId,
UserId = input.UserId
};
core.SemesterDetails = new List<StudentSemesterCore>();
foreach (var items in input.SemesterDetails)
{
core.SemesterDetails.Add(new StudentSemesterCore()
{
GPA = items.GPA,
MarkPercentage = items.MarkPercentage,
Status = items.Status,
UserId = items.UserId ,
Id = items.Id,
StudentDegreeID = items.StudentDegreeID ,
YearOrSemester = items.YearOrSemester,
LastModificationTime = DateTime.Now,
CreationTime = DateTime.Now
});
}
var student = core; //ObjectMapper.Map<StudentDegreeCore>(input);
long uid = (AbpSession.UserId == null) ? 0 : Convert.ToInt64(AbpSession.UserId);
st = _studentRepository.Get(student.Id);
if (st != null && st.Id > 0)
{
st.DegreeCollege = student.DegreeCollege;
st.CollegeID = student.CollegeID;
st.CommencementYear = student.CommencementYear;
st.CompletionYear = student.CompletionYear;
st.LastModificationId = Convert.ToInt32(AbpSession.UserId);
st.LastModificationTime = DateTime.Now;
st.StreamId = student.StreamId;
st.DegreeId = student.DegreeId;
st.CurrentYear = student.CurrentYear;
st.OverallPercent = student.OverallPercent;
st.PinCode = student.PinCode;
st.PostBox = student.PostBox;
st.State = student.State;
st.Address1 = student.Address1;
st.Address2 = student.Address2;
st.City = student.City;
st.SemesterDetails = new List<StudentSemesterCore>();
//st.SemesterDetails = student.SemesterDetails;
_studentRepository.Update(st);
foreach (var items in student.SemesterDetails)
{
_studentSemesterRepository.InsertOrUpdate(items);
}
//_studentRepository.Update(st);
CurrentUnitOfWork.SaveChanges();
}
else
{
student.UserId = Convert.ToInt32(AbpSession.UserId);
student.CreationId = Convert.ToInt32(AbpSession.UserId);
_studentRepository.Insert(student);
CurrentUnitOfWork.SaveChanges();
}
}
catch (Exception ex)
{
}
StudentDegreeDto studentDegreeDto = new StudentDegreeDto()
{
Id = input.Id,
Address1 = input.Address1,
Address2 = input.Address2,
City = input.City,
CollegeID = input.CollegeID,
CommencementYear = input.CommencementYear,
CompletionYear = input.CompletionYear,
CurrentYear = input.CurrentYear,
DegreeCollege = input.DegreeCollege,
DegreeId = input.DegreeId,
OverallPercent = input.OverallPercent,
PinCode = input.PinCode,
PostBox = input.PostBox,
State = input.State,
StreamId = input.StreamId,
UserId = input.UserId
};
studentDegreeDto.SemesterDetails = new List<StudentSemesterDto>();
foreach (var items in input.SemesterDetails)
{
studentDegreeDto.SemesterDetails.Add(new StudentSemesterDto()
{
GPA = items.GPA,
MarkPercentage = items.MarkPercentage,
Status = items.Status,
YearOrSemester = items.YearOrSemester,
LastModificationTime = DateTime.Now,
CreationTime = DateTime.Now
});
}
return studentDegreeDto;
}
I have a model as below
public class Lesson
{
public int Id { get; set; }
public Section Div { get; set; }
}
public class Section
{
public int Id { get; set; }
public string Name { get; set; }
}
I also have DB Context as below
public class MyContext : DbContext
{
public MyContext() : base("DefaultConnection")
{
this.Configuration.LazyLoadingEnabled = false;
this.Configuration.ProxyCreationEnabled = false;
}
public DbSet<Lesson> Lessons { get; set; }
public DbSet<Section> Sections { get; set; }
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
base.OnModelCreating(modelBuilder);
}
}
Then I use the following code to call the database
using (MyContext c = new EFTest.MyContext())
{
Lesson d = new EFTest.Lesson();
Section ed = new EFTest.Section() { Name = "a" };
d.Div = ed;
c.Entry(d.Div).State = EntityState.Detached;
c.Lessons.Add(d);
c.SaveChanges();
}
I am expecting this code to save just the Lesson object, not to save the full graph of Lesson and Section, but what happens is that it saves the full graph.
How do I prevent it from doing that?
When you add an entity to DbSet, entityframework will add all of its relative. You need to detach the entity you don't want to add, after adding parent entity to DbSet.
using (MyContext c = new EFTest.MyContext())
{
Lesson d = new EFTest.Lesson();
Section ed = new EFTest.Section() { Name = "a" };
d.Div = ed;
c.Lessons.Add(d);
c.Entry(d.Div).State = EntityState.Detached;
c.SaveChanges();
}
if you want to add section, related to the lesson , you need to use the same context, or create a new context and load the lesson.
you can use this code
using (MyContext c = new EFTest.MyContext())
{
Lesson d = new EFTest.Lesson();
Section ed = new EFTest.Section() { Name = "a" };
d.Div = ed;
c.Lessons.Add(d);
c.Entry(d.Div).State = EntityState.Detached;
c.SaveChanges();
//you can use this code
ed.Lesson = d;
// or this code
d.Div = ed;
c.Sections.Add(ed);
c.SaveChanges();
}
I wrote this code
class Student {
public Student() {
this.Courses = new HashSet<Course>();
}
public int ID { get; set; }
public string Name { get; set; }
public virtual ICollection<Course> Courses { get; set; }
}
class Course {
public Course() {
this.Students = new HashSet<Student>();
}
public int ID { get; set; }
public string Name { get; set; }
public virtual ICollection<Student> Students { get; set; }
}
class SchoolDBContext : DbContext {
public DbSet<Student> Students { get; set; }
public DbSet<Course> Courses { get; set; }
public SchoolDBContext()
: base("SchoolDbConnectionString") {
}
protected override void OnModelCreating(DbModelBuilder modelBuilder) {
modelBuilder.Conventions.Remove<PluralizingTableNameConvention>();
}
}
My Seed method looks like
protected override void Seed(ConsoleApplication6.SchoolDBContext context)
{
Course c1 = new Course { ID = 1, Name = "Chemistry" };
Course c2 = new Course { ID = 2, Name = "Maths" };
Course[] courses = new Course[2];
courses[0] = c1;
courses[1] = c2;
Student s1 = new Student { ID = 1, Name = "Student 1" };
Student s2 = new Student { ID = 1, Name = "Student 2" };
Student[] students = new Student[2];
students[0] = s1;
students[1] = s2;
c1.Students = students;
c2.Students = students;
context.Courses.AddOrUpdate(course => new { course.ID }, courses);
}
After I run Update-database I can see that the database has 3 tables. Student and Course tables have 2 rows each and StudentCourse table has 4 rows. So I guess all data is seeded correctly.
Now when I write this code in my main method
static void Main(string[] args) {
SchoolDBContext c = new SchoolDBContext();
c.Configuration.LazyLoadingEnabled = true;
Student s = (from student in c.Students where student.ID == 1 select student).FirstOrDefault();
List<Course> courses = s.Courses.ToList();
Console.WriteLine(s.Name);
Console.WriteLine(courses.Count);
foreach (Course co in courses) {
Console.WriteLine(co.Name);
}
}
it prints the name of the student correctly... but prints 0 for courses.Count and the forloop on courses List returns nothing.
why am I not able to get the courses for student 1?
I also tried the other way round
static void Main(string[] args) {
SchoolDBContext c = new SchoolDBContext();
c.Configuration.LazyLoadingEnabled = true;
Course co = (from course in c.Courses where course.ID == 1 select course).FirstOrDefault();
Console.WriteLine(co.Name);
List<Student> students = co.Students.ToList();
foreach (Student s in students) {
Console.WriteLine(s.Name);
}
}
here also the name of the course is returned correctly... but it doesn't print any of the students.
So entity framework is not able to walk to the related table and fetch rows from there.
What's going on?
Found the answer myself.
static void Main(string[] args) {
SchoolDBContext c = new SchoolDBContext();
c.Configuration.LazyLoadingEnabled = false;
Course co = (from course in c.Courses.Include("Students") where course.ID == 1 select course).FirstOrDefault();
Console.WriteLine(co.Name);
List<Student> students = co.Students.ToList();
foreach (Student s in students) {
Console.WriteLine(s.Name);
}
}
putting it here so that it benefits someone....
But according to me my original code should have worked (lazy loading) so I don't understand why my original code which was doing lazy loading did not work.
OK. here is the solution with lazy loading
static void Main(string[] args) {
SchoolDBContext context = new SchoolDBContext();
context.Configuration.LazyLoadingEnabled = true;
Course co = (from course in context.Courses where course.ID == 1 select course).FirstOrDefault();
//Course co = (from course in c.Courses where course.ID == 1 select course).FirstOrDefault();
Console.WriteLine(co.Name);
foreach (Student s in context.Entry(co).Collection(c => c.Students).Query()) {
Console.WriteLine(s.Name);
}
}
This was really useful
http://msdn.microsoft.com/en-us/data/jj574232#lazy
In debugging the issue in this thread: InvalidCastException when querying nested collection with LINQ I found out that something is wrong with how my Category EntitySet is populated. After selecteding a Category and throwing this exception to see what's going on I get this:
throw new Exception("CID: " + cat.CategoryID +
" LCID: " + cat.LocalizedCategories.First().LocalizedCategoryID +
" CID from LC: " + cat.LocalizedCategories.First().Category.CategoryID);
CID: 352 LCID: 352 CID from LC: 191
What am I doing wrong that causes CategoryID to have different values depending on how I LINQ to it? It should be 191, and not the same value as the LocalizedCategoryID.
This is the code I use to get the Category:
int categoryId = 352; // In reality this comes from a parameter and is supposed
// to be 191 to get the Category.
var cat = categoriesRepository.Categories.First(c => c.CategoryID == categoryId);
This is my domain object with some unrelated stuff stripped:
[Table(Name = "products")]
public class Product
{
[HiddenInput(DisplayValue = false)]
[Column(Name = "id", IsPrimaryKey = true, IsDbGenerated = true, AutoSync = AutoSync.OnInsert)]
public int ProductID { get; set; }
[Required(ErrorMessage = "Please enter a product name")]
[Column]
public string Name { get; set; }
[Required(ErrorMessage = "Please enter a description")]
[DataType(DataType.MultilineText)]
[Column(Name = "info")]
public string Description { get; set; }
private EntitySet<Category> _Categories = new EntitySet<Category>();
[System.Data.Linq.Mapping.Association(Storage = "_Categories", OtherKey = "CategoryID")]
public ICollection<Category> Categories
{
get { return _Categories; }
set { _Categories.Assign(value); }
}
}
[Table(Name = "products_types")]
public class Category
{
[HiddenInput(DisplayValue = false)]
[Column(Name = "id", IsPrimaryKey = true, IsDbGenerated = true, AutoSync = AutoSync.OnInsert)]
public int CategoryID { get; set; }
public string NameByCountryId(int countryId)
{
return _LocalizedCategories.Single(lc => lc.CountryID == countryId).Name;
}
private EntitySet<LocalizedCategory> _LocalizedCategories = new EntitySet<LocalizedCategory>();
[System.Data.Linq.Mapping.Association(Storage = "_LocalizedCategories", OtherKey = "LocalizedCategoryID")]
public ICollection<LocalizedCategory> LocalizedCategories
{
get { return _LocalizedCategories; }
set { _LocalizedCategories.Assign(value); }
}
private EntitySet<Product> _Products = new EntitySet<Product>();
[System.Data.Linq.Mapping.Association(Storage = "_Products", OtherKey = "ProductID")]
public ICollection<Product> Products
{
get { return _Products; }
set { _Products.Assign(value); }
}
}
[Table(Name = "products_types_localized")]
public class LocalizedCategory
{
[HiddenInput(DisplayValue = false)]
[Column(Name = "id", IsPrimaryKey = true, IsDbGenerated = true, AutoSync = AutoSync.OnInsert)]
public int LocalizedCategoryID { get; set; }
[Column(Name = "products_types_id")]
private int CategoryID;
private EntityRef<Category> _Category = new EntityRef<Category>();
[System.Data.Linq.Mapping.Association(Storage = "_Category", ThisKey = "CategoryID")]
public Category Category
{
get { return _Category.Entity; }
set { _Category.Entity = value; }
}
[Column(Name = "country_id")]
public int CountryID { get; set; }
[Column]
public string Name { get; set; }
}
This (in class Category) looks weird:
[System.Data.Linq.Mapping.Association(Storage = "_LocalizedCategories",
OtherKey = "LocalizedCategoryID" )] // ????
public ICollection<LocalizedCategory> LocalizedCategories
Category has a collection of LocalizedCategorys, which means that in the database the table products_types_localized has a foreign keyCategoryID. That field should be the "OtherKey". How was this mapping generated?