private async Task UnEnrollSteveFromCourse(ManyToManyContext ctx)
{
StudentCourse steveAndDnp = ctx.Students.
Where(s => s.StudentNum == 123456).
SelectMany(student => student.StudentCourses).
First(studentCourse => studentCourse.Course.CourseCode.Equals("IT-SDJ2-A20"));
ctx.Remove(steveAndDnp);
await ctx.SaveChangesAsync();
}
private static async Task AddOneSteve(ManyToManyContext ctx)
{
Student s = new Student
{
FirstName = "Steve",
LastName = "Doe",
Email = "*****@*****.**",
StudentNum = 123456
};
await ctx.Students.AddAsync(s);
await ctx.SaveChangesAsync();
}
private static async Task WhichCoursesIsSteveEnrolledIn(ManyToManyContext ctx)
{
List <Course> courses = await ctx.Students
.Where(s => s.StudentNum == 123456)
.SelectMany(student => student.StudentCourses)
.Select(studentCourse => studentCourse.Course)
.ToListAsync();
foreach (var course in courses)
{
Console.WriteLine(course);
}
}
private static async Task EnrollSteveInDNP(ManyToManyContext ctx, string course)
{
Student steve = await ctx.Students.FirstAsync(s => s.StudentNum == 123456);
Course dnp = await ctx.Courses.FirstAsync(c => c.CourseCode.Equals(course));
StudentCourse sc = new StudentCourse
{
Course = dnp,
Student = steve
};
ctx.Set <StudentCourse>().Add(sc);
await ctx.SaveChangesAsync();
}
protected override void Seed(ManyToManyContext context)
{
base.Seed(context);
ChangesDate = new DateTime(2010, 1, 1);
context.RemoveRange(context.ChangeTracker.Entries().Where(e => e.Entity is EntityThree).Select(e => e.Entity));
context.RemoveRange(context.ChangeTracker.Entries().Where(e => e.Entity is EntityTwo).Select(e => e.Entity));
context.RemoveRange(context.ChangeTracker.Entries().Where(e => e.Entity is EntityOne).Select(e => e.Entity));
context.RemoveRange(context.ChangeTracker.Entries().Where(e => e.Entity is EntityCompositeKey).Select(e => e.Entity));
context.RemoveRange(context.ChangeTracker.Entries().Where(e => e.Entity is EntityRoot).Select(e => e.Entity));
context.SaveChanges();
var tableNames = new List <string>
{
"EntityCompositeKeys",
"EntityOneEntityTwo",
"EntityOnes",
"EntityTwos",
"EntityThrees",
"EntityRoots",
"EntityRootEntityThree",
"JoinCompositeKeyToLeaf",
"EntityCompositeKeyEntityRoot",
"JoinOneSelfPayload",
"JoinOneToBranch",
"JoinOneToThreePayloadFull",
"JoinOneToThreePayloadFullShared",
"JoinOneToTwo",
"JoinThreeToCompositeKeyFull",
"EntityTwoEntityTwo",
"EntityCompositeKeyEntityTwo",
"JoinTwoToThree",
};
foreach (var tableName in tableNames)
{
context.Database.ExecuteSqlRaw($"ALTER TABLE [{tableName}] SET (SYSTEM_VERSIONING = OFF)");
context.Database.ExecuteSqlRaw($"ALTER TABLE [{tableName}] DROP PERIOD FOR SYSTEM_TIME");
context.Database.ExecuteSqlRaw($"UPDATE [{tableName + "History"}] SET PeriodStart = '2000-01-01T01:00:00.0000000Z'");
context.Database.ExecuteSqlRaw($"UPDATE [{tableName + "History"}] SET PeriodEnd = '2020-07-01T07:00:00.0000000Z'");
context.Database.ExecuteSqlRaw($"ALTER TABLE [{tableName}] ADD PERIOD FOR SYSTEM_TIME ([PeriodStart], [PeriodEnd])");
context.Database.ExecuteSqlRaw(
$"ALTER TABLE [{tableName}] SET (SYSTEM_VERSIONING = ON (HISTORY_TABLE = [dbo].[{tableName + "History"}]))");
}
}
static void TryManyToManyContext()
{
using (var context = new ManyToManyContext())
{
Artist artist1 = new Artist()
{
FirstName = "Mihai",
LastName = "Luca",
};
Album album1 = new Album
{
Name = "Blue Flower",
Date = DateTime.Now
};
AlbumArtist albumArtist1 = new AlbumArtist
{
Album = album1,
Artist = artist1
};
context.Artists.Add(artist1);
context.Albums.Add(album1);
context.AlbumArtists.Add(albumArtist1);
context.SaveChanges();
foreach (var artist in context.Artists)
{
Console.WriteLine($"Name:{artist.FirstName} {artist.LastName}");
foreach (var albumArtist in artist.AlbumArtists)
{
Console.WriteLine($"Name: {albumArtist.Album.Name} Date: {albumArtist.Album.Date}");
}
}
}
}
private static async Task AddTwoCourses(ManyToManyContext ctx)
{
Course sdj2 = new Course
{
Abbreviation = "SDJ2",
Name = "Software Development with UML and Java 2",
Semester = 2,
CourseCode = "IT-SDJ2-A20",
ECTS = 10
};
Course dnp1 = new Course
{
Abbreviation = "DNP1",
Name = "I forgot the actual name",
Semester = 3,
CourseCode = "IT-DNP1Y-A20",
ECTS = 5
};
await ctx.Courses.AddAsync(sdj2);
await ctx.Courses.AddAsync(dnp1);
await ctx.SaveChangesAsync();
}
static async Task Main(string[] args)
{
using (ManyToManyContext context = new ManyToManyContext())
await WhichCoursesIsSteveEnrolledIn(context);
}
