var blogs = context.Blogs
    .FromSql("SELECT * FROM dbo.Blogs")
    .ToList();

var blogs = context.Blogs
  .FromSql("EXECUTE dbo.GetMostPopularBlogs")
  .ToList();

var user = "johndoe";

var blogs = context.Blogs
  .FromSql("EXECUTE dbo.GetMostPopularBlogsForUser {0}", user)
  .ToList();

var user = new SqlParameter("user", "johndoe");
var blogs = context.Blogs
  .FromSql("EXECUTE dbo.GetMostPopularBlogsForUser @user", user)
  .ToList();

 var results = _context.Contacts.FromSql(
@"SELECT Id, Name Address, City, State, Zip 
    FROM Contacts 
    WHERE Name IN (@p0, @p1)", name1, name2);

var nameParameter = new SqlParameter
{
  ParameterName = "@name",
  Value = "doc",
  Direction = ParameterDirection.Input,
  SqlDbType = SqlDbType.NVarChar
};

var posts = context.Posts
  .FromSql("SELECT * FROM dbo.GetMatchingPostByTitle({0})", searchTerm)
  .Where(p => p.BlogId == 1)
  .OrderByDescending(p => p.CreateDate)
  .ToList();

var searchTerm = ".NET";
var blogs = context.Blogs
  .FromSql("SELECT * FROM dbo.SearchBlogs {0}", searchTerm)
  .Include(b => b.Posts)
  .ToList();

  context.Database.ExecuteSqlCommand("UPDATE dbo.People SET FirstName = 'Jane' WHERE PersonId = 30");

context.Database.ExecuteSqlCommand("usp_CreateShipper @p0, @p1",
  parameters: new[] { "hello", "world" });

using (var connection = context.Database.GetDbConnection())
{
    connection.Open();
 
    using (var command = connection.CreateCommand())
    {
        command.CommandText = "SELECT COUNT(*) FROM Contacts";
        var result = command.ExecuteScalar().ToString();
    }
}

var userName = "user 1";
var user = context.Users.FromSql($"select top 1 * from Users where name = {userName} ").FirstOrDefault();
if (user != null)
{
   Console.WriteLine(user.Name);
}

SELECT TOP(1) [u].[UserId], [u].[IsAdmin], [u].[Name]
FROM (
    select top 1 * from Users where name = @p0
) AS [u]

var sql = $"select top 1 * from Users where name = {userName} ";
user = context.Users.FromSql(sql).FirstOrDefault();
if (user != null)
{
   Console.WriteLine(user.Name);
}

 .SqlException: Incorrect syntax near '1'

 public static IQueryable<TEntity> FromSql<TEntity>(this IQueryable<TEntity> source, FormattableString sql) where TEntity : class;

 var sql = $"select top 1 * from Users where name = '{userName}' ";

SELECT TOP(1) [u].[UserId], [u].[IsAdmin], [u].[Name]
FROM (
   select top 1 * from Users where name = 'user 1'
) AS [u]

var blogs = from blog in Blogs
   where blog.Name.Contains("Development")
   select blog;

var blogs = from blog in Blogs
   where blog.Name.ComputeHash() == 0
   select blog;

public class Blog
{
   public int BlogId { get; set; }
   public string Url { get; set; }  
}

    public static class StringExtensions
    {
        public static int ComputeHash(this string str)
        {
            var hash = 0;
            foreach (var ch in str)
            {
                hash += (int)ch;
            }
            return hash;
        }
    }

using (var context = new BloggingContext())
{
   var blogs = context.Blogs
     .Where(blog => blog.Url.ComputeHash() >= 10)
     .ToList();
   Console.WriteLine(blogs.First().Url);
}

SELECT [blog].[BlogId], [blog].[Url]
   FROM [Blogs] AS [blog]

var idUrls = context.Blogs
   .Select(b => new
   {
      IdUrlString = string.Join(", ", b.BlogId, b.Url),
   }).ToList();

    public class BloggingContext : DbContext
    {
        public BloggingContext()
        { }

        public BloggingContext(DbContextOptions options)
            : base(options)
        { }

        public DbSet<Blog> Blogs { get; set; }

        protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
        {
            if (!optionsBuilder.IsConfigured)
            {
                optionsBuilder.UseSqlServer(@"Server=(localdb)\mssqllocaldb;Database=Demo.ClientSideEvaluation;Trusted_Connection=True;");
                optionsBuilder.ConfigureWarnings(warnings =>
                {
                    warnings.Log(CoreEventId.IncludeIgnoredWarning);
                    warnings.Log(RelationalEventId.QueryClientEvaluationWarning);
                });
            }
        }
    }

 warn: Microsoft.EntityFrameworkCore.Query[200500]
The LINQ expression 'where ([blog].Url.ComputeHash() >= 10)' could not be translated and will be evaluated locally.

var idUrls2 = context.Blogs
   .Select(b => new
   {
     IdUrlString = b.BlogId + "," + b.Url
   }).ToList();

SELECT (CAST([b].[BlogId] AS nvarchar(max)) + N',') + [b].[Url] AS [IdUrlString]
FROM [Blogs] AS [b]

using (var db = new BloggingContext())
{
   var blog = new Blog { Url = "http://sample.com" };
   db.Blogs.Add(blog);
   db.SaveChanges();
}

using (var db = new BloggingContext())
{
  var blog = db.Blogs.First();
  blog.Url = "http://sample.com/blog";
  db.SaveChanges();
}

using (var db = new BloggingContext())
{
  var blog = db.Blogs.First();
  db.Blogs.Remove(blog);
  db.SaveChanges();
}

using (var context = new BloggingContext())
{
   var blog = context.Blogs
      .Select(b =>
            new
            {
               Blog = b,
               Posts = b.Posts.Count()
            });
 }

using (var context = new BloggingContext())
{
   var blog = context.Blogs
            .Select(b =>
                 new
                 {
                   Id = b.BlogId,
                   Url = b.Url
                 });
 }

using (var context = new BloggingContext())
{
  var blogs = context.Blogs.AsNoTracking().ToList();
}

using (var context = new BloggingContext())
{
    context.ChangeTracker.QueryTrackingBehavior = QueryTrackingBehavior.NoTracking;

using (var context = new BloggingContext())
{
  var blog = context.Blogs.First();
  var post = new Post { Title = "Intro to EF Core" };

  blog.Posts.Add(post);
  context.SaveChanges();
}

using (var context = new BloggingContext())
{
  var blog = new Blog { Url = "http://blogs.msdn.com/visualstudio" };
  var post = context.Posts.First();

  blog.Posts.Add(post);
  context.SaveChanges();
}

 var blog = new Blog { Id = 2, Url = "https://www.dntips.ir" };
 context.Blog.Attach(blog);
 context.SaveChanges();

 var blog = new Blog { Id = 2, Url = "https://www.dntips.ir" };
 context.Entry(blog).State = EntityState.Modified ;
 context.SaveChanges();

 var blog = new Blog { Id = 2, Url = "https://www.dntips.ir" };
 context.Update(blog);
 context.SaveChanges();

 context.ChangeTracker.TrackGraph(blog, e => e.Entry.State = EntityState.Added);

public class BaseEntity
{
   public int Id { set; get; }
   public DateTime? DateAdded { set; get; }
   public DateTime? DateUpdated { set; get; }
}

public class Person : BaseEntity
{
   public string FirstName { get; set; }
   public string LastName { get; set; }
}

    public class ApplicationDbContext : DbContext
    {
        // same as before 

        public override int SaveChanges()
        {
            this.ChangeTracker.DetectChanges();

            var modifiedEntries = this.ChangeTracker
                                      .Entries<BaseEntity>()
                                      .Where(x => x.State == EntityState.Modified);
            foreach (var modifiedEntry in modifiedEntries)
            {
                modifiedEntry.Entity.DateUpdated = DateTime.UtcNow;
            }
 
            var addedEntries = this.ChangeTracker
                                      .Entries<BaseEntity>()
                                      .Where(x => x.State == EntityState.Added);
            foreach (var addedEntry in addedEntries)
            {
                addedEntry.Entity.DateAdded = DateTime.UtcNow;
            }
 
            return base.SaveChanges();
        }
    }

protected override void OnModelCreating(ModelBuilder modelBuilder)
{
  modelBuilder.Entity<Blog>().Property<DateTime>("DateAdded");

 var blogs = context.Blogs.OrderBy(b => EF.Property<DateTime>(b, "DateAdded"));

 context.Entry(myBlog).Property("DateAdded").CurrentValue = DateTime.Now;

foreach (var addedEntry in addedEntries)
{
  addedEntry.Property("DateAdded").CurrentValue = DateTime.UtcNow;
}

public class Student
{
    public int Id { get; set; }
 
    [Required]
    [StringLength(450)]
    public string LastName { get; set; }
 
    [Required]
    [StringLength(450)]
    public string FirstName { get; set; }
 
    [NotMapped]
    public string FullName
    {
        get
        {
            return LastName + ", " + FirstName;
        }
    }
}

 var fullNames = context.Students.Select(x => x.FullName).ToList();

 var fullNames = context.Students.Select(x => x.FullName).Decompile().ToList();

SELECT
           [Extent1].[LastName] + N', ' + [Extent1].[FirstName] AS [C1]
FROM [dbo].[Students] AS [Extent1]

[NotMapped]
[Computed]
public string FullName

public class StudentViewModel
{
    public int Id { get; set; }
    public string FullName { get; set; }
}

 var students = context.Students.Project().To<StudentViewModel>().ToList();

var students = context.Students
    .Project()
    .To<StudentViewModel>()
    .Decompile()
    .ToList();

SELECT
    [Extent1].[Id] AS [Id],
    [Extent1].[LastName] + N', ' + [Extent1].[FirstName] AS [C1]
FROM [dbo].[Students] AS [Extent1]

    public class User
    {
        public int Id { get; set; }
        public string Name { get; set; }

        public virtual ICollection<BlogPost> BlogPosts { get; set; }
    }

    public class BlogPost
    {
        public int Id { get; set; }
        public string Title { get; set; }
        public string Content { get; set; }

        [ForeignKey("UserId")]
        public virtual User User { get; set; }
        public int UserId { get; set; }
    }

 var data = context.BlogPosts.ToList();

 var data = context.BlogPosts.ToList();

 var list = context.BlogPosts.Select(x => x.Content).Skip(15).Take(15).ToList();

 foreach (var post in context.BlogPosts)
{
     Console.WriteLine(post.User.Name);
}

 foreach (var post in context.BlogPosts.Include(x=>x.User))

 var data = context.BlogPosts.ToList();

 var data = context.BlogPosts.AsNoTracking().Skip(15).Take(15).ToList();

        private void problem5MoreThan1ConnectionPerRequest() 
        {
            using (var context = new MyContext())
            {
                var count = context.BlogPosts.ToList();
            }
        }

DataContext = from user in context.Users
                      where user.Id>10
                      select user;

 var list = context.BlogPosts.Where(x => x.Content.Contains("test"))