static void Main(string[] args)
{
var _dbContext = new PersonHistoryContext();
// method syntax
var bornPeopleNames = _dbContext.Person
.AsNoTracking()
.Where(person => person.Birth.BirthDate < DateTime.Now)
.Select(person => person.NameFirst)
.ToList();
bornPeopleNames.ForEach(name => Console.WriteLine(name));
// query syntax
var bornPeopleNamesQuery =
from p in _dbContext.Person.AsNoTracking()
where p.Birth.BirthDate < DateTime.Now
select p.NameFirst;
bornPeopleNamesQuery.ToList().ForEach(name => Console.WriteLine(name));
// get birthday for specific person
var johnaldBirthday = _dbContext.Person
.AsNoTracking()
.Where(person => person.NameFirst == "Johnald")
.Select(person => person.Birth.BirthDate)
.FirstOrDefault();
Console.WriteLine(johnaldBirthday.ToString());
// what about the whole object?
var johnaldBirthdayObject = _dbContext.Person
.AsNoTracking()
.Where(person => person.NameFirst == "Johnald")
.Select(person => person.Birth)
.FirstOrDefault();
Console.WriteLine(johnaldBirthdayObject.BirthDate.ToString());
// what if we want Johnald AND his birthday?
var johnaldWithBirthday = _dbContext.Person
.AsNoTracking()
.FirstOrDefault(person => person.NameFirst == "Johnald");
Console.WriteLine(johnaldWithBirthday.NameFirst);
if (johnaldWithBirthday.Birth != null)
{
Console.WriteLine(johnaldWithBirthday.Birth.BirthDate.ToString());
}
else
{
Console.WriteLine("Not quite");
}
// this is the way
var johnaldWithBirth = _dbContext.Person
.AsNoTracking()
.Include(person => person.Birth)
.FirstOrDefault(person => person.NameFirst == "Johnald");
Console.WriteLine(johnaldWithBirthday.NameFirst);
Console.WriteLine(johnaldWithBirth.Birth.BirthDate.ToString());
// still works
var johnaldOldSchool = _dbContext.Person
.FromSqlRaw($"SELECT * FROM Person p WHERE p.name_first = 'Johnald'")
.AsNoTracking()
.Single();
Console.WriteLine("Mr. " + johnaldOldSchool.NameLast);
// not so much
var johnaldOldSchoolQuestionMark = _dbContext.Person
.FromSqlRaw($"SELECT p.name_first FROM Person p WHERE p.name_first = 'Johnald'")
.AsNoTracking()
.Single();
Console.WriteLine("Mr. " + johnaldOldSchoolQuestionMark.NameLast);
}
static void Main(string[] args)
{
// CREATE/READ
var dbContext = new PersonHistoryContext();
var johnBirth = new Birth
{
Id = 1234, // not using generated IDs -> defaults to 0
BirthDate = DateTime.Now
};
var john = new Person
{
Id = 1234, // not using generated IDs -> defaults to 0
NameFirst = "John",
NameLast = "Doe",
Birth = johnBirth
};
dbContext.Add(johnBirth);
dbContext.Add(john);
var newJohn = dbContext.Person
.FirstOrDefault();
dbContext.SaveChanges();
newJohn = dbContext.Person
.FirstOrDefault();
// UPDATE
var misterDoeBirth = new Birth
{
Id = 1233,
BirthDate = (DateTime.Now).AddYears(-30).AddDays(3)
};
var misterDoe = new Person
{
Id = 1233,
NameFirst = "Johnald",
NameLast = "Doe",
Birth = misterDoeBirth
};
newJohn.Father = misterDoe;
dbContext.SaveChanges();
newJohn = dbContext.Person
.FirstOrDefault(person => person.Id == 1234);
Console.WriteLine(newJohn != null ? newJohn.Father.NameFirst : "Luke is not your father");
// DELETE
dbContext.Person
.Remove(newJohn);
dbContext.SaveChanges();
var johnQuestionMark = dbContext.Person
.FirstOrDefault(person => person.Id == 1234);
Console.WriteLine(johnQuestionMark != null ? "JOHN! You're alive!" : ":rip:");
}
