public void Deleting_Principal_With_Include_Will_Remove_Dependent()
{
// Populate data
using (var context = new OtmContext(ContextOptions, IsRequired))
{
context.Blogs.AddRange(GenerateData());
context.SaveChanges();
}
// Update post through its principal
using (var context = new OtmContext(ContextOptions, IsRequired))
{
var blog = context.Blogs.Include(b => b.Posts).FirstOrDefault(b => b.Url == "https://timheuer.com/blog/");
Assert.IsNotNull(blog);
context.Blogs.Remove(blog);
context.SaveChanges();
}
using (var context = new OtmContext(ContextOptions, IsRequired))
{
// Blog is removed
var blog = context.Blogs.FirstOrDefault(b => b.Url == "https://timheuer.com/blog/");
Assert.IsNull(blog);
// Post IS REMOVED
var post = context.Posts.FirstOrDefault(p => p.Title.Contains("Deploying .NET Core 3"));
Assert.IsNull(post);
}
}
public void Deleting_DEPENDENT_Has_No_Effect_On_Principal()
{
// Populate data
using (var context = new OtmContext(ContextOptions, IsRequired))
{
context.Blogs.AddRange(GenerateData());
context.SaveChanges();
}
// Update post through its principal
using (var context = new OtmContext(ContextOptions, IsRequired))
{
var post = context.Posts.FirstOrDefault(p => p.Title.Contains("Deploying .NET Core 3"));
Assert.IsNotNull(post);
context.Posts.Remove(post);
context.SaveChanges();
}
using (var context = new OtmContext(ContextOptions, IsRequired))
{
// Post is deleted
var post = context.Posts.FirstOrDefault(p => p.Title.Contains("Deploying .NET Core 3"));
Assert.IsNull(post);
// PRincipal not removed
var blog = context.Blogs.FirstOrDefault(b => b.Url == "https://timheuer.com/blog/");
Assert.IsNotNull(blog);
}
}
public void Can_Update_Dependent_Alone()
{
// Populate data
using (var context = new OtmContext(ContextOptions, IsRequired))
{
context.Blogs.AddRange(GenerateData());
context.SaveChanges();
}
// Update post through its principal
using (var context = new OtmContext(ContextOptions, IsRequired))
{
var post = context.Posts.FirstOrDefault(p => p.Title.Contains("Deploying .NET Core 3"));
Assert.IsNotNull(post);
post.Title = "Deploying .NET 5 apps as self-contained";
context.SaveChanges();
}
using (var context = new OtmContext(ContextOptions, IsRequired))
{
var post = context.Posts.FirstOrDefault(p => p.Title.Contains("Deploying .NET 5 apps"));
Assert.IsNotNull(post);
}
}
public void Deleting_Principal_Will_Remove_Dependent()
{
// Populate data
using (var context = new OtmContext(ContextOptions, IsRequired))
{
context.Blogs.AddRange(GenerateData());
context.SaveChanges();
}
// Update post through its principal
using (var context = new OtmContext(ContextOptions, IsRequired))
{
var blog = context.Blogs.FirstOrDefault(b => b.Url == "https://timheuer.com/blog/");
Assert.IsNotNull(blog);
context.Blogs.Remove(blog);
context.SaveChanges();
}
// Dependent entities are removed
using (var context = new OtmContext(ContextOptions, IsRequired))
{
var blog = context.Blogs.FirstOrDefault(b => b.Url == "https://timheuer.com/blog/");
Assert.IsNull(blog);
var post1 = context.Posts.FirstOrDefault(p => p.Title == "Deploying .NET Core 3 apps as self-contained");
Assert.IsNull(post1);
var post2 = context.Posts.FirstOrDefault(p => p.Title == "Skipping CI in GitHub Actions Workflows");
Assert.IsNull(post2);
}
}
public void Can_Update_Dependent_Through_Principal_With_Include()
{
// Populate data
using (var context = new OtmContext(ContextOptions, IsRequired))
{
context.Blogs.AddRange(GenerateData());
context.SaveChanges();
}
// Update post through its principal
using (var context = new OtmContext(ContextOptions, IsRequired))
{
var blog = context.Blogs.Include(b => b.Posts).FirstOrDefault(b => b.Url == "https://timheuer.com/blog/");
Assert.IsNotNull(blog);
Assert.IsNotNull(blog.Posts);
var post = blog.Posts.FirstOrDefault(p => p.Title.Contains("Deploying .NET Core 3"));
Assert.IsNotNull(post);
post.Title = "Deploying .NET 5 apps as self-contained";
context.SaveChanges();
}
using (var context = new OtmContext(ContextOptions, IsRequired))
{
var post = context.Posts.FirstOrDefault(p => p.Title.Contains("Deploying .NET 5 apps"));
Assert.IsNotNull(post);
}
}
public void Deleting_Principal_With_Include_SUCCEED_Has_No_Effect_On_Dependent()
{
// Populate data
using (var context = new OtmContext(ContextOptions, IsRequired))
{
context.Blogs.AddRange(GenerateData());
context.SaveChanges();
}
// Update post through its principal
using (var context = new OtmContext(ContextOptions, IsRequired))
{
var blog = context.Blogs.Include(b => b.Posts).FirstOrDefault(b => b.Url == "https://timheuer.com/blog/");
Assert.IsNotNull(blog);
context.Blogs.Remove(blog);
context.SaveChanges();
}
using (var context = new OtmContext(ContextOptions, IsRequired))
{
// Blog is removed
var blog = context.Blogs.FirstOrDefault(b => b.Url == "https://timheuer.com/blog/");
Assert.IsNull(blog);
// Post still alive
var post = context.Posts.FirstOrDefault(p => p.Title.Contains("Deploying .NET Core 3"));
Assert.IsNotNull(post);
var post2 = context.Posts.FirstOrDefault(p => p.Title == "Skipping CI in GitHub Actions Workflows");
Assert.IsNotNull(post2);
}
}
public void Can_NOT_Create_Dependent_Without_Principal()
{
using (var context = new OtmContext(ContextOptions, IsRequired))
{
var post = new Post {
Title = "Test Post", Content = "No content"
};
context.Posts.Add(post);
Assert.That(() => context.SaveChanges(), Throws.Exception);
}
}
public void Can_Create_Principal_Without_Dependent()
{
using (var context = new OtmContext(ContextOptions, IsRequired))
{
var blog = new Blog {
Url = "https://medium.com/@bc"
};
context.Blogs.Add(blog);
context.SaveChanges();
}
using (var context = new OtmContext(ContextOptions, IsRequired))
{
var blog = context.Blogs.FirstOrDefault(b => b.Url == "https://medium.com/@bc");
Assert.IsNotNull(blog);
}
}
public void Can_Create_Dependent_Without_Principal()
{
using (var context = new OtmContext(ContextOptions, IsRequired))
{
var post = new Post {
Title = "Test Post", Content = "No content"
};
context.Posts.Add(post);
context.SaveChanges();
}
using (var context = new OtmContext(ContextOptions, IsRequired))
{
var post = context.Posts.FirstOrDefault(p => p.Title == "Test Post");
Assert.IsNotNull(post);
}
}
public void Deleting_Principal_FAILS_Without_Including_Dependent()
{
// Populate data
using (var context = new OtmContext(ContextOptions, IsRequired))
{
context.Blogs.AddRange(GenerateData());
context.SaveChanges();
}
// Delete fails for principal entity because it needs to have navigation property loaded to set FK to NULL.
using (var context = new OtmContext(ContextOptions, IsRequired))
{
var blog = context.Blogs.FirstOrDefault(b => b.Url == "https://timheuer.com/blog/");
Assert.IsNotNull(blog);
context.Blogs.Remove(blog);
Assert.That(() => context.SaveChanges(), Throws.Exception);
}
}
public void Can_NOT_Update_Dependent_Through_Principal_Without_Include()
{
// Populate data
using (var context = new OtmContext(ContextOptions, IsRequired))
{
context.Blogs.AddRange(GenerateData());
context.SaveChanges();
}
// Update post through its principal
using (var context = new OtmContext(ContextOptions, IsRequired))
{
var blog = context.Blogs.FirstOrDefault(b => b.Url == "https://timheuer.com/blog/");
Assert.IsNotNull(blog);
// Since it is initialized by default, dependent is not null
Assert.IsNotNull(blog.Posts);
Assert.AreEqual(0, blog.Posts.Count);
}
}
public void Can_Create_Dependent_With_Principal_Only()
{
using (var context = new OtmContext(ContextOptions, IsRequired))
{
var post = new Post {
Title = "Test Post", Content = "No content", Blog = new Blog {
Url = "https://medium.com"
}
};
context.Posts.Add(post);
context.SaveChanges();
}
using (var context = new OtmContext(ContextOptions, IsRequired))
{
var post = context.Posts.Include(p => p.Blog).FirstOrDefault(p => p.Title == "Test Post");
Assert.IsNotNull(post);
Assert.IsNotNull(post.Blog);
}
}
public static void Run(DbContextOptions options, bool isRequired = false)
{
Console.WriteLine("----- CREATE -----");
using (var context = new OtmContext(options, isRequired))
{
context.Database.EnsureDeleted();
context.Database.EnsureCreated();
//
Console.Write("Creating a new blog w/o posts");
var blog1 = new Blog {
Url = "http://blogs.msdn.com/adonet"
};
context.Blogs.Add(blog1);
context.SaveChanges();
Console.WriteLine("==> Done.");
Console.Write("Creating a new blog with posts");
var blog2 = new Blog {
Url = "https://wordpress.com"
};
blog2.Posts.AddRange(
new List <Post>
{
new Post {
Title = "My first app", Content = "I wrote an app using EF Core 1"
},
new Post {
Title = "My second app", Content = "I wrote an app using EF Core 2"
}
});
context.Blogs.Add(blog2);
context.SaveChanges();
Console.WriteLine("==> Done");
//
Console.Write("Creating post w/o blog");
var post3 = new Post {
Title = "EF Core Tutorial", Content = "Getting started with EF Core"
};
context.Posts.Add(post3);
try
{
context.SaveChanges();
Console.WriteLine("==> Done");
}
catch (Exception)
{
context.Entry(post3).State = EntityState.Detached;
context.Posts.Remove(post3);
Console.WriteLine("==> FAILED: Can not save post w/o blog. Provide a required relationship.");
}
//
Console.Write("Creating a post w/ blog");
var post4 = new Post
{
Title = "Swift tutorial",
Content = "Learn how to code Swift.",
Blog = new Blog {
Url = "https://medium.com/@bc/swift"
}
};
context.Posts.Add(post4);
try
{
context.SaveChanges();
Console.WriteLine("==> Done");
}
catch (Exception)
{
context.Entry(post4).State = EntityState.Detached;
context.Posts.Remove(post4);
Console.WriteLine("==>FAILED: Can not save the post w/ blog");
}
}
Console.WriteLine("----- QUERY -----");
using (var context = new OtmContext(options, isRequired))
{
Console.Write("Querying for a blog w/o post");
var foundBlog1 = context.Blogs.First(b => b.Url == "http://blogs.msdn.com/adonet");
if (foundBlog1 != null)
{
Console.WriteLine("==> Done: Blog1 with Url{0} found", "http://blogs.msdn.com/adonet");
}
else
{
Console.WriteLine("==> Failed: Can not find Blog with Url: {0}", "http://blogs.msdn.com/adonet");
}
//
Console.Write("Querying for a blog w posts");
var foundBlog2 = context.Blogs.FirstOrDefault(b => b.Url == "https://wordpress.com");
if (foundBlog2 == null)
{
Console.WriteLine("Not found. Querying with .Include() method.");
foundBlog2 = context.Blogs.Include(b => b.Posts).FirstOrDefault(b => b.Url == "https://wordpress.com");
}
Console.WriteLine("==> Done: Blog w/ Posts with Url{0} found", foundBlog2.Url);
//
Console.Write("Querying for post w/o blog");
var foundPost1 = context.Posts.FirstOrDefault(p => p.Title == "EF Core Tutorial");
if (foundPost1 != null)
{
Console.WriteLine("==> Done: Post w/ blog is found. Title: {0}", foundPost1.Title);
}
else
{
Console.WriteLine("==> Failed: Can not find post w/ blog.");
}
//
Console.Write("Querying for a post w blog");
var foundPost2 = context.Posts.FirstOrDefault(p => p.Blog.Url == "https://medium.com/@bc/swift");
if (foundPost2 == null)
{
Console.WriteLine("Can not find the post w/ blog. Using .Include()");
foundPost2 = context.Posts.Include(p => p.Blog).FirstOrDefault(p => p.Blog.Url == "https://medium.com/@bc/swift");
}
Console.WriteLine("==> Done: Post w blog is found");
}
Console.WriteLine("----- UPDATE -----");
using (var context = new OtmContext(options, isRequired))
{
Console.Write("Update a blog w/o post by adding a post");
var foundBlog1 = context.Blogs.FirstOrDefault(b => b.Url == "http://blogs.msdn.com/adonet");
foundBlog1.Posts.Add(
new Post {
Title = "How to create Hello, World app in C++", Content = "This is a very very long story"
}
);
context.SaveChanges();
Console.Write("==>Done");
Console.Write("Update a blog's post");
// Need to include navigation property
var foundBlog2 = context.Blogs.Include(b => b.Posts).FirstOrDefault(b => b.Url == "https://wordpress.com");
foundBlog2.Posts.Add(new Post {
Title = "Smart pointers in C++", Content = "Smart pointers are sometimes life-savers...."
});
context.SaveChanges();
Console.WriteLine("==> Done");
Console.Write("Updating a post w/o blog by adding a blog");
var foundPost1 = context.Posts.FirstOrDefault(p => p.Title == "EF Core Tutorial");
if (foundPost1 == null)
{
Console.WriteLine("==> FAILED: Can not find the post w/o a blog record. Make sure the relationship is optional");
}
else
{
foundPost1.Blog = new Blog {
Url = "https://medium.com/@someone/do-coding"
};
context.SaveChanges();
Console.WriteLine("==> Done: Post w/o blog is found and updated");
}
Console.Write("Updating a post w/ blog");
var foundPost2 = context.Posts.Include(p => p.Blog).FirstOrDefault(p => p.Blog.Url == "https://medium.com/@bc/swift");
if (foundPost2 == null)
{
Console.WriteLine("==> FAILED: Can not find a post w/ blog Url: {0}", "https://medium.com/@bc/swift");
}
else
{
foundPost2.Title = "Do some Swift stuff";
context.SaveChanges();
Console.WriteLine("==> Done: The post w/ blog is found and updated");
}
}
Console.WriteLine("----- DELETE -----");
using (var context = new OtmContext(options, isRequired))
{
// Delete
Console.Write("Delete a blog w/ post");
var foundBlog = context.Blogs.Include(b => b.Posts).FirstOrDefault(b => b.Posts.Any(p => p.Title == "How to create Hello, World app in C++"));
if (foundBlog == null)
{
Console.WriteLine("==>FAILED: Can not find a blog w/ post titled: {0}", "How to create Hello, World app in C++");
}
else
{
// this will remove the dependent posts if the relationship is required.
context.Blogs.Remove(foundBlog);
context.SaveChanges();
Console.WriteLine("==> Done: Blog is removed");
}
Console.Write("Delete a post w/blog");
// since post is dependent, it does not affect its principal entity
var foundPost = context.Posts.FirstOrDefault(p => p.Title == "My first app");
if (foundPost == null)
{
Console.WriteLine("==> Can not find a post w/ blog titled My first app");
}
else
{
context.Posts.Remove(foundPost);
context.SaveChanges();
Console.WriteLine("==> Done: The post titled My first app is removed from the database");
}
}
}