public static void LoadSelection()
{
using var ctx = CourseDbContextFactory.GetSQLCourseContext();
var result = ctx.Courses.Select(c => new
{
c.CourseId,
c.Title,
commentCount = c.Comments.Count,
}).ToList();
}
public static void LoadEager01()
{
using var ctx = CourseDbContextFactory.GetSQLCourseContext();
var data = ctx.Courses.Where(c => c.Price > 100)
.Include(c => c.Discount)
.Include(c => c.Comments.Take(10))
.Include(c => c.Teachers).ThenInclude(c => c.Teacher)
.Include(c => c.Tags).ToList();
}
public static void voidClientVsServer()
{
using var ctx = CourseDbContextFactory.GetSQLCourseContext();
//ctx.Teachers.OrderBy(c => c.FullName).Take(10); Error
var course = ctx.Courses.Select(c => new
{
c.Title,
TagsString = string.Join(',', c.Tags.Select(t => t.Title))
});
}
public static void LoadExplicti01()
{
using var ctx = CourseDbContextFactory.GetSQLCourseContext();
var courses = ctx.Courses.Where(c => c.Price > 100).ToList();
foreach (var course in courses)
{
ctx.Entry(course).Reference(c => c.Discount).Load();
ctx.Entry(course).Collection(c => c.Comments).Query();
}
}
public CourseDbContext CreateDbContext(string[] args)
{
return(CourseDbContextFactory.GetSQLCourseContext());
}
public static void SeedData()
{
using var ctx = CourseDbContextFactory.GetSQLCourseContext();
ctx.Database.EnsureDeleted();
ctx.Database.EnsureCreated();
var course01 = new Course()
{
Title = "Pro ASP.NET 5",
Description = "Advanced Course About .NET 5 Platform",
Price = 12_000_000,
Comments = new List <Comment>()
{
new Comment()
{
CommentBy = "Mr. Alaki",
CommentText = "It's Nice!"
},
new Comment()
{
CommentBy = "Ms. Palaki",
CommentText = "Wow! Amazing!"
}
},
StartDate = DateTime.Now
};
var course02 = new Course()
{
Title = "DevOps in Action",
Description = "Advanced Course About DevOps World!",
Price = 120_000_000,
Comments = new List <Comment>()
{
new Comment()
{
CommentBy = "Mr. Alaki",
CommentText = "Nice course about devops!"
},
new Comment()
{
CommentBy = "Ms. Palaki",
CommentText = "Wonderful!"
}
},
StartDate = DateTime.Now
};
var teacher01 = new Teacher()
{
FirstName = "Alireza",
LastName = "Oroumand",
};
var teacher02 = new Teacher()
{
FirstName = "Mohamad",
LastName = "Abbasi",
};
var tag01 = new Tag()
{
Title = "programming",
Courses = new List <Course>()
{
course01
}
};
var tag02 = new Tag()
{
Title = "infrastructure",
Courses = new List <Course>()
{
course02
}
};
var courseTeacher01 = new CourseTeacher()
{
Course = course01,
Teacher = teacher01
};
var courseTeacher02 = new CourseTeacher()
{
Course = course02,
Teacher = teacher02
};
ctx.Add(course01);
ctx.Add(course02);
ctx.Add(teacher01);
ctx.Add(teacher02);
ctx.Add(courseTeacher01);
ctx.Add(courseTeacher02);
ctx.Add(tag01);
ctx.Add(tag02);
ctx.SaveChanges();
}
}
}
public static void Collate()
{
using var ctx = CourseDbContextFactory.GetSQLCourseContext();
ctx.Courses.Where(x => EF.Functions.Collate(x.Title, "Latin1_General_CS_AS") == "HELP");
}