public static void ADONET_DataAdapter()
{
CUI.MainHeadline(nameof(ADONET_DataAdapter));
var connstring = new WWWingsContext().Database.GetDbConnection().ConnectionString;
DbProviderFactory factory =
DbProviderFactories.GetFactory("System.Data.SqlClient");
SqlConnection connection = new SqlConnection(connstring);
using (connection)
{
SqlDataAdapter adapter = new SqlDataAdapter(
"SELECT * FROM dbo.Flight", connection);
SqlCommandBuilder builder = new SqlCommandBuilder(adapter);
Console.WriteLine(builder.GetUpdateCommand().CommandText);
}
}
public static void RelationshipFixUp_Case2()
{
CUI.MainHeadline(nameof(RelationshipFixUp_Case2));
void PrintPilot(Pilot pilot)
{
CUI.PrintSuccess(pilot.ToString());
if (pilot.FlightAsPilotSet != null)
{
Console.WriteLine("Flights of this pilot:");
foreach (var f in pilot.FlightAsPilotSet)
{
Console.WriteLine(f);
}
}
else
{
CUI.PrintWarning("No flights!");
}
}
using (var ctx = new WWWingsContext())
{
// Load a Pilot
var pilot = ctx.PilotSet.FirstOrDefault();
// Print pilot and his flights
PrintPilot(pilot);
// Create a new flight for this pilot
var flight = new Flight();
flight.Departure = "Berlin";
flight.Destination = "Berlin";
flight.Date = DateTime.Now.AddDays(10);
flight.FlightNo = ctx.FlightSet.Max(x => x.FlightNo) + 1;
flight.PilotId = pilot.PersonID;
ctx.FlightSet.Add(flight);
// this does not help: ctx.ChangeTracker.DetectChanges();
// Print pilot and his flights
PrintPilot(pilot);
// Print pilot of the new flight
Console.WriteLine(flight.Pilot);
}
}
public static void RemoveFlightWithKey()
{
Console.WriteLine(nameof(RemoveFlightWithKey));
using (WWWingsContext ctx = new WWWingsContext())
{
// Create a dummy object
var f = new Flight();
f.FlightNo = 123456;
Console.WriteLine($"After creation: Flight #{f.FlightNo}: {f.Departure}->{f.Destination} has {f.FreeSeats} free seats! State of the flight object: " + ctx.Entry(f).State);
// Append dummy object to context
ctx.Attach(f);
Console.WriteLine($"After attach: Flight #{f.FlightNo}: {f.Departure}->{f.Destination} has {f.FreeSeats} free seats! State of the flight object: " + ctx.Entry(f).State);
// Delete flight
ctx.FlightSet.Remove(f);
// or: ctx.Remove(f);
Console.WriteLine($"After remove: Flight #{f.FlightNo}: {f.Departure}->{f.Destination} has {f.FreeSeats} free seats! State of the flight object: " + ctx.Entry(f).State);
try
{
var anz = ctx.SaveChanges();
if (anz == 0)
{
Console.WriteLine("Problem: No changes saved!");
}
else
{
Console.WriteLine("Number of saved changes: " + anz);
}
Console.WriteLine($"After saving: Flight #{f.FlightNo}: {f.Departure}->{f.Destination} has {f.FreeSeats} free seats! State of the flight object: " + ctx.Entry(f).State);
}
catch (Exception ex)
{
Console.WriteLine("Error: " + ex.ToString());
}
}
}
public static void Demo_RelationhipFixup1N()
{
CUI.MainHeadline(nameof(Demo_RelationhipFixup1N));
using (var ctx = new WWWingsContext())
{
// Load a flight
var flight101 = ctx.FlightSet.SingleOrDefault(x => x.FlightNo == 101);
Console.WriteLine($"Flight Nr {flight101.FlightNo} from {flight101.Departure} to {flight101.Destination} has {flight101.FreeSeats} free seats!");
// Load the pilot for this flight with the list of his flights
var oldPilot = ctx.PilotSet.Include(x => x.FlightAsPilotSet).SingleOrDefault(x => x.PersonID == flight101.PilotId);
Console.WriteLine("Pilot: " + oldPilot.PersonID + ": " + oldPilot.GivenName + " " + oldPilot.Surname + " has " + oldPilot.FlightAsPilotSet.Count + " flights as pilot!");
// Next pilot in the list load with the list of his flights
var newPilot = ctx.PilotSet.Include(x => x.FlightAsPilotSet).SingleOrDefault(x => x.PersonID == flight101.PilotId + 1);
Console.WriteLine("Planned Pilot: " + newPilot.PersonID + ": " + newPilot.GivenName + " " + newPilot.Surname + " has " + newPilot.FlightAsPilotSet.Count + " flights as pilot!");
// Assign to Flight
CUI.Print("Assignment of the flight to the planned pilot...", ConsoleColor.Cyan);
newPilot.FlightAsPilotSet.Add(flight101);
// optional:force Relationship Fixup
// ctx.ChangeTracker.DetectChanges();
CUI.Print("Output before saving: ", ConsoleColor.Cyan);
Console.WriteLine("Old pilot: " + oldPilot.PersonID + ": " + oldPilot.GivenName + " " + oldPilot.Surname + " has " + oldPilot.FlightAsPilotSet.Count + " flights as a pilot!");
Console.WriteLine("New pilot: " + newPilot.PersonID + ": " + newPilot.GivenName + " " + newPilot.Surname + " has " + newPilot.FlightAsPilotSet.Count + " flights as a pilot!");
var pilotAktuell = flight101.Pilot; // Current Pilot in the Flight object
Console.WriteLine("Pilot for flight " + flight101.FlightNo + " is currently: " + pilotAktuell.PersonID + ": " + pilotAktuell.GivenName + " " + pilotAktuell.Surname);
// SaveChanges()()
CUI.Print("Saving... ", ConsoleColor.Cyan);
var count = ctx.SaveChanges();
CUI.MainHeadline("Number of saved changes: " + count);
CUI.Print("Output after saving: ", ConsoleColor.Cyan);
Console.WriteLine("Old Pilot: " + oldPilot.PersonID + ": " + oldPilot.GivenName + " " + oldPilot.Surname + " has " + oldPilot.FlightAsPilotSet.Count + " flights as pilot!");
Console.WriteLine("New Pilot: " + newPilot.PersonID + ": " + newPilot.GivenName + " " + newPilot.Surname + " has " + newPilot.FlightAsPilotSet.Count + " flights as pilot!");
pilotAktuell = flight101.Pilot; // Current pilot from the perspective of the Flight object
Console.WriteLine("Pilot for Flight " + flight101.FlightNo + " is now: " + pilotAktuell.PersonID + ": " + pilotAktuell.GivenName + " " + pilotAktuell.Surname);
}
}
public static void Projection_EntityType()
{
using (var ctx = new WWWingsContext())
{
CUI.MainHeadline(nameof(Projection_EntityType));
var q = (from f in ctx.FlightSet
where f.FlightNo > 100
orderby f.FlightNo
select new Flight()
{
FlightNo = f.FlightNo,
Date = f.Date,
Departure = f.Departure,
Destination = f.Destination,
FreeSeats = f.FreeSeats,
Timestamp = f.Timestamp
}).Take(2);
var flightSet = q.ToList();
foreach (var f in flightSet)
{
Console.WriteLine($"Flight Nr {f.FlightNo} from {f.Departure} to {f.Destination} has {f.FreeSeats} free seats!");
}
Console.WriteLine("Number of flights: " + flightSet.Count);
foreach (var f in flightSet)
{
Console.WriteLine("Before attach: " + f + " State: " + ctx.Entry(f).State + " Timestamp: " + ByteArrayToString(f.Timestamp));
ctx.Attach(f);
Console.WriteLine("After attach: " + f + " State: " + ctx.Entry(f).State + " Timestamp: " + ByteArrayToString(f.Timestamp));
f.FreeSeats--;
Console.WriteLine("After Änderung: " + f + " State: " + ctx.Entry(f).State + " Timestamp: " + ByteArrayToString(f.Timestamp));
var count = ctx.SaveChanges();
Console.WriteLine("Number of saved changes: " + count);
Console.WriteLine("After saving: " + f + " State: " + ctx.Entry(f).State + " Timestamp: " + ByteArrayToString(f.Timestamp));
}
}
}
public static void LINQ_ToString()
{
CUI.MainHeadline(nameof(LINQ_ToString));
using (var ctx = new WWWingsContext())
{
ctx.Log();
var q1 = from p in ctx.FlightSet
where p.FlightNo < 10
orderby p.FreeSeats
select p;
EntityQueryable <Flight> q1b = (EntityQueryable <Flight>)q1;
Console.WriteLine(q1.ToString()); // EF: returns SQL. EFC: returns type :-(
Console.WriteLine(q1b.ToString()); // EF: returns SQL. EFC: returns type :-(
}
}
public static void LINQ_Find()
{
CUI.MainHeadline(nameof(LINQ_Find));
using (var ctx = new WWWingsContext())
{
ctx.FlightSet.ToList(); // Caching all flights in context (here as an example only to show the caching effect!)
var flightNo = 101;
var f = ctx.FlightSet.Find(flightNo); // Flight is loaded from cache!
if (f != null)
{
Console.WriteLine($"Flight Nr {f.FlightNo} from {f.Departure} to {f.Destination} has {f.FreeSeats} free seats!");
}
else
{
Console.WriteLine("Flight not found!");
}
} // End using-Block -> Dispose()
}
public static void GeneratedSQL()
{
CUI.MainHeadline(nameof(GeneratedSQL));
var ctx = new WWWingsContext();
var flightSet1 = ctx.FlightSet.ToList();
var flightSet2 = ctx.FlightSet.Where(f2 => f2.Departure == "Rome").ToList();
var flightSet3 = (from f3 in ctx.FlightSet
where f3.Departure.StartsWith("M")
select f3)
.ToList();
var flightSet4 = (from f4 in ctx.FlightSet
where f4.Departure.StartsWith("M")
orderby f4.FlightNo
select f4).Skip(5).Take(10).ToList();
}
public static void TrackGraph()
{
CUI.MainHeadline(nameof(TrackGraph));
Flight f;
using (WWWingsContext ctx1 = new WWWingsContext())
{
int flightNo = 150;
f = ctx1.FlightSet.Include(x => x.Pilot).Where(x => x.FlightNo == flightNo).SingleOrDefault();
Console.WriteLine(f);
Console.WriteLine(f.Pilot);
}
using (WWWingsContext ctx2 = new WWWingsContext())
{
ctx2.ChangeTracker.TrackGraph(f, TrackGraph_Callback);
var anz = ctx2.SaveChanges();
Console.WriteLine(anz + " Changes saved!");
}
}
public static void Kontextwechselproblem()
{
Flight flight101;
using (var ctx1 = new WWWingsContext())
{
// Lade einen Flight
flight101 = ctx1.FlightSet.Include(f => f.Pilot).SingleOrDefault(x => x.FlightNo == 101);
Console.WriteLine($"Flight Nr {flight101.FlightNo} from {flight101.Departure} to {flight101.Destination} has {flight101.FreeSeats} free seats! Pilot: " + flight101.Pilot);
}
using (var ctx2 = new WWWingsContext())
{
// Lade einen Flight
var pilot = ctx2.PilotSet.Find(flight101.PilotId + 1);
flight101.Pilot = pilot;
Console.WriteLine("Neuer Pilot: " + pilot.ToString());
var count = ctx2.SaveChanges();
Console.WriteLine(count + " Changes saved!");
}
}
private void C_Test_Click(object sender, RoutedEventArgs e)
{
try
{
ctx = new WWWingsContext();
var flight = ctx.FlightSet.FirstOrDefault();
if (flight == null)
{
MessageBox.Show("No flights :-(", "Test Connection", MessageBoxButton.OK, MessageBoxImage.Warning);
}
else
{
MessageBox.Show("OK!", "Test Connection", MessageBoxButton.OK, MessageBoxImage.Information);
}
}
catch (Exception ex)
{
MessageBox.Show("Error: " + ex.ToString(), "Test Connection", MessageBoxButton.OK, MessageBoxImage.Error);
}
}
/// <summary>
/// Variante 3 UNSINNIG !!!
/// Wenn Concurrency Check nicht auf Timestamp, sondern auf Wertespalten (außer Timestamp) aktiv, gehen Varianten 1 und 2 nicht, weil EF die neuen Werte auch als Originalwerte annehmen wird und die nicht in DB finden kann
/// Hier wird aber fehlerhafterweise der Inhalt der DB nochmal gelesen, weil den Concurreny Check absurd macht
/// </summary>
public static void Detached_Flight_ConcurrencyCheck_AusDB()
{
CUI.MainHeadline(nameof(Detached_Flight_ConcurrencyCheck_AusDB));
Flight flight;
CUI.Print("Lade Objekt in Kontextinstanz #1");
using (WWWingsContext ctx1 = new WWWingsContext())
{
ctx1.Log();
//ctx1.Configuration.LazyLoadingEnabled = false;
flight = ctx1.FlightSet.Find(110);
}
CUI.Print("Objekt ändern");
CUI.Print(flight.ToString());
flight.FreeSeats--;
flight.Date = flight.Date.AddHours(2);
CUI.Print(flight.ToString());
CUI.Print("Objekt nun speichern mit Kontextinstanz #2");
using (WWWingsContext ctx2 = new WWWingsContext())
{
ctx2.Log();
// Wegen des Concurreny Checks brauchen wir die Originalwerte entweder aus dem Objekt selbst oder der DB
// Aus DB ist aber keine gute Lösung, denn damit ist der Concurreny Check auf den Spalten unsinnig
// hier aus DB
var flightOrg = ctx2.FlightSet.Find(110);
CUI.Print(ctx2.Entry(flightOrg).State.ToString());
// Nun Werte des alten Objekts auf das neue kopieren
ctx2.Entry(flightOrg).CurrentValues.SetValues(flight);
CUI.Print(ctx2.Entry(flightOrg).State.ToString());
var count = ctx2.SaveChanges();
Console.WriteLine("Saved changes: " + count.ToString());
if (count != 1)
{
Debugger.Break();
}
}
}
public static void GetFlight_StandardCache_Aendern(string departure = "Rome")
{
using (var ctx = new WWWingsContext())
{
ctx.Log();
CUI.Headline($"Alle Flights from {departure} laden!");
// Alle Flights laden
var flightSet = ctx.FlightSet.Where(x => x.Departure == departure && x.FlightNo < 200).ToList();
var flightNo = 190; // FlightSet 190 ist ein FlightSet from Rom, der schon geladen wurde // flightSet.ElementAt
// Ein Objekt wird im RAM geändert
var flightSetImRAM = flightSet.FirstOrDefault(x => x.FlightNo == flightNo);
CUI.Print("FlightSet Before changes: " + flightSetImRAM?.ToShortString(), ConsoleColor.White);
flightSetImRAM.FreeSeats--;
CUI.Print("FlightSet to der Änderung: " + flightSetImRAM?.ToShortString(), ConsoleColor.White);
// Dann wird das Objekt neu geladen!
CUI.Headline("Ein FlightSet laden mit Find() - allein aus Cache!");
var flight1 = ctx.FlightSet.Find(flightNo);
CUI.Print(flight1?.ToShortString(), ConsoleColor.White);
CUI.Headline("Ein FlightSet laden mit SingleOrDefault() -> Query!");
var flight2 = ctx.FlightSet.SingleOrDefault(x => x.FlightNo == flightNo);
CUI.Print(flight2?.ToShortString(), ConsoleColor.White);
CUI.Headline("Ein FlightSet laden mit FirstOrDefault() -> Query!");
var flight3 = ctx.FlightSet.FirstOrDefault(x => x.FlightNo == flightNo);
CUI.Print(flight3?.ToShortString(), ConsoleColor.White);
CUI.Headline("Ein FlightSet laden mit where/SingleOrDefault() -> Query!");
var flight4 = ctx.FlightSet.Where(x => x.FlightNo == flightNo).SingleOrDefault();
CUI.Print(flight4.ToShortString(), ConsoleColor.White);
CUI.Headline("Cacheinhalt");
foreach (var f in ctx.FlightSet.Local)
{
Console.WriteLine(f.ToShortString());
}
}
}
public static void Demo_EagerLoading()
{
CUI.MainHeadline(nameof(Demo_EagerLoading));
using (var ctx = new WWWingsContext())
{
var flightNo = 101;
// Load the flight and some connected objects via Eager Loading
var f = ctx.FlightSet
.Include(b => b.BookingSet).ThenInclude(p => p.Passenger)
.Include(b => b.Pilot).ThenInclude(p => p.FlightAsPilotSet)
.Include(b => b.Copilot).ThenInclude(p => p.FlightAsCopilotSet)
.SingleOrDefault(x => x.FlightNo == flightNo);
Console.WriteLine($"Flight Nr {f.FlightNo} from {f.Departure} to {f.Destination} has {f.FreeSeats} free seats!");
if (f.Pilot != null)
{
Console.WriteLine($"Pilot: {f.Pilot.Surname} has {f.Pilot.FlightAsPilotSet.Count} flights as a pilot!");
}
else
{
Console.WriteLine("No pilot assigned!");
}
if (f.Copilot != null)
{
Console.WriteLine($"Copilot: {f.Copilot.Surname} has {f.Copilot.FlightAsCopilotSet.Count} flights as a Copilot!");
}
else
{
Console.WriteLine("No Copilot assigned!");
}
Console.WriteLine("Number of passengers on this flight: " + f.BookingSet.Count);
Console.WriteLine("Passengers on this flight:");
foreach (var b in f.BookingSet)
{
Console.WriteLine("- Passenger #{0}: {1} {2}", b.Passenger.PersonID, b.Passenger.GivenName, b.Passenger.Surname);
}
}
}
public static void TrackingMode_QueryTrackingBehavior()
{
CUI.MainHeadline("Default setting: TrackAll. Use AsNoTracking()");
using (WWWingsContext ctx = new WWWingsContext())
{
ctx.ChangeTracker.QueryTrackingBehavior = QueryTrackingBehavior.TrackAll; // is default
var flightSet = ctx.FlightSet.AsNoTracking().ToList();
var flight = flightSet[0];
Console.WriteLine(flight + " object state: " + ctx.Entry(flight).State); // Detached
flight.FreeSeats--;
Console.WriteLine(flight + " object state: " + ctx.Entry(flight).State); // Detached
int count = ctx.SaveChanges();
Console.WriteLine($"Saved changes: {count}"); // 1
}
CUI.MainHeadline("Default setting: NoTracking.");
using (WWWingsContext ctx = new WWWingsContext())
{
ctx.ChangeTracker.QueryTrackingBehavior = QueryTrackingBehavior.NoTracking; // NoTracking
var flightSet = ctx.FlightSet.ToList();
var flight = flightSet[0];
Console.WriteLine(flight + " object state: " + ctx.Entry(flight).State); // Detached
flight.FreeSeats--;
Console.WriteLine(flight + " object state: " + ctx.Entry(flight).State); // Detached
int count = ctx.SaveChanges();
Console.WriteLine($"Saved changes: {count}"); // 1
}
CUI.MainHeadline("Default setting: NoTracking. Use AsTracking()");
using (WWWingsContext ctx = new WWWingsContext())
{
ctx.ChangeTracker.QueryTrackingBehavior = QueryTrackingBehavior.NoTracking; // NoTracking
var flightSet = ctx.FlightSet.AsTracking().ToList();
var flight = flightSet[0];
Console.WriteLine(flight + " object state: " + ctx.Entry(flight).State); // Unchanged
flight.FreeSeats--;
Console.WriteLine(flight + " object state: " + ctx.Entry(flight).State); // Modified
int count = ctx.SaveChanges();
Console.WriteLine($"Saved changes: {count}"); // 1
}
}
public static void LINQ_SingleOrDefault()
{
CUI.MainHeadline(nameof(LINQ_SingleOrDefault));
using (var ctx = new WWWingsContext())
{
var flightNo = 101;
var f = (from x in ctx.FlightSet
where x.FlightNo == flightNo
select x).SingleOrDefault();
if (f != null)
{
Console.WriteLine($"Flight Nr {f.FlightNo} from {f.Departure} to {f.Destination} has {f.FreeSeats} free seats!");
}
else
{
Console.WriteLine("Flight not found!");
}
} // End using-Block -> Dispose()
}
public static void EreignisFolge()
{
var ctx1 = new WWWingsContext();
CUI.Print("1. Kontext 1. Abfrage");
ctx1.FlightSet.FirstOrDefault();
CUI.Print("1. Kontext 2. Abfrage");
ctx1.FlightSet.FirstOrDefault();
var ctx2 = new WWWingsContext();
CUI.Print("2. Kontext 1. Abfrage");
ctx2.FlightSet.FirstOrDefault();
CUI.Print("2. Kontext 2. Abfrage");
ctx2.FlightSet.FirstOrDefault();
var ctx3 = new WWWingsContext();
CUI.Print("3. Kontext 1. Abfrage");
ctx3.FlightSet.FirstOrDefault();
CUI.Print("3. Kontext 2. Abfrage");
ctx3.FlightSet.FirstOrDefault();
}
public static void ClearCache()
{
using (var ctx = new WWWingsContext())
{
ctx.Log();
CUI.Headline("Load 5 Flights and Pilots...");
ctx.FlightSet.Take(5).ToList();
ctx.PilotSet.Take(5).ToList();
Console.WriteLine("Flights in Cache: " + ctx.FlightSet.Local.Count);
Console.WriteLine("Pilots in Cache: " + ctx.PilotSet.Local.Count);
foreach (var f in ctx.FlightSet.Local.ToList())
{
ctx.Entry(f).State = EntityState.Detached;
}
Console.WriteLine("Flights in Cache: " + ctx.FlightSet.Local.Count);
Console.WriteLine("Pilots in Cache: " + ctx.PilotSet.Local.Count);
}
}
public static void BulkDeleteEFCAPIwithBatching()
{
CUI.Headline(nameof(BulkDeleteEFCAPIwithBatching));
int total = 0;
var sw = new Stopwatch();
sw.Start();
using (var ctx = new WWWingsContext())
{
var min = 20000;
var flightSet = ctx.FlightSet.Where(x => x.FlightNo >= min).ToList();
foreach (Flight f in flightSet)
{
ctx.FlightSet.Remove(f);
}
total = ctx.SaveChanges();
}
sw.Stop();
Console.WriteLine("Number of DELETE statements: " + total);
Console.WriteLine("Duration: " + sw.ElapsedMilliseconds);
}
public static void LINQ_CustomFunction()
{
CUI.MainHeadline("Query with Custom Function - RAM :-(");
using (var ctx = new WWWingsContext())
{
var q4 = from f in ctx.FlightSet
where f.FreeSeats > 0 &&
GetNumberOfDaysUntil(f.Date) > 10
orderby f.FlightNo
select f;
List <Flight> l4 = q4.Take(10).ToList();
Console.WriteLine("Count: " + l4.Count);
foreach (var f in l4)
{
Console.WriteLine(f);
}
}
}
public static void TransactionScopeDemo()
{
CUI.Headline(nameof(TransactionScopeDemo));
using (var t = new TransactionScope())
{
using (var ctx1 = new WWWingsContext())
{
int flightNo = ctx1.FlightSet.OrderBy(x => x.FlightNo).FirstOrDefault().FlightNo;
var f = ctx1.FlightSet.Where(x => x.FlightNo == flightNo).SingleOrDefault();
Console.WriteLine("Before: " + f.ToString());
f.FreeSeats--;
f.Memo = "Last changed at " + DateTime.Now.ToString();
Console.WriteLine("After: " + f.ToString());
var count1 = ctx1.SaveChanges();
Console.WriteLine("Number of saved changes: " + count1);
}
using (var ctx2 = new WWWingsContext())
{
var f = ctx2.FlightSet.OrderBy(x => x.FlightNo).Skip(1).Take(1).SingleOrDefault();
Console.WriteLine("Before: " + f.ToString());
f.FreeSeats--;
f.Memo = "Last changed at " + DateTime.Now.ToString();
Console.WriteLine("After: " + f.ToString());
var count1 = ctx2.SaveChanges();
Console.WriteLine("Number of saved changes: " + count1);
}
// Commit Transaction!
t.Complete();
CUI.PrintSuccess("Completed!");
}
}
public static void GroupBy_SQL_NonEntityType()
{
// Get the number of flights per Departure
using (var ctx = new WWWingsContext())
{
// Map SQL to non-entity class
Console.WriteLine(ctx.Database.GetType().FullName);
ctx.Log();
var sql = "SELECT Departure, COUNT(FlightNo) AS FlightCount FROM Flight GROUP BY Departure";
// ERROR!!! Cannot create a DbSet for 'Group' because this type is not included in the model for the context."
var groupSet = ctx.Set <DepartureGroup>().FromSql(sql);
// Output
foreach (var g in groupSet)
{
Console.WriteLine(g.Departure + ": " + g.FlightCount);
}
}
return;
// Groupy by "nested"
using (var ctx = new WWWingsContext())
{
ctx.Log();
var groupSet = from p in ctx.FlightSet
orderby p.FreeSeats
group p by p.Departure into g
select g;
Console.WriteLine("Count: " + groupSet.Count());
foreach (var g in groupSet)
{
Console.WriteLine(g.Key + ": " + g.Count());
foreach (var f in g)
{
Console.WriteLine(" " + f.FlightNo);
}
}
}
}
public static void RelationshipFixup_Run()
{
CUI.Headline("RelationshipFixup/First Level Cache");
using (WWWingsContext ctx = new WWWingsContext())
{
ctx.Log();
var pilot = ctx.PilotSet.Find(1030);
Console.WriteLine("Pilot: " + pilot.PersonID);
pilot = null;
// Möglich: Löschen aus Cache
// ctx.Pilot.Local.Clear(); somit würde es wirklich weg sein!
// or: ctx.Pilot.Local.Remove(pilot); VOR DEM SETZEN AUF NULL!
// der Pilot sollte nun weg sein
var flight = ctx.FlightSet.Find(101);
// ist er aber nicht !!!
Console.WriteLine(flight);
Console.WriteLine("Pilot dieses flightSets: " + flight.Pilot.PersonID);
}
}
public static void ShowUpdatedTimeStamp()
{
CUI.MainHeadline(nameof(ShowUpdatedTimeStamp));
using (WWWingsContext ctx = new WWWingsContext())
{
var f = ctx.FlightSet.Take(1).SingleOrDefault();
Console.WriteLine("Before: " + f.ToString() + " Timestamp: " + f.Timestamp.ByteArrayToString());
f.FreeSeats--; // Change #1
Console.WriteLine("After change: " + f.ToString() + " Timestamp: " + f.Timestamp.ByteArrayToString());
var anz1 = ctx.SaveChanges();
Console.WriteLine("After saving: " + f.ToString() + " Timestamp: " + f.Timestamp.ByteArrayToString());
CUI.PrintSuccess("Number of saved changes: " + anz1);
Console.WriteLine("Before: " + f.ToString() + " Timestamp: " + f.Timestamp.ByteArrayToString());
f.FreeSeats--; // Change #2
Console.WriteLine("After change: " + f.ToString() + " Timestamp: " + f.Timestamp.ByteArrayToString());
var anz2 = ctx.SaveChanges();
Console.WriteLine("After saving: " + f.ToString() + " Timestamp: " + f.Timestamp.ByteArrayToString());
CUI.PrintSuccess("Number of saved changes: " + anz2);
}
}
public static void Demo_PreLoadingPilotsCaching()
{
CUI.MainHeadline(nameof(Demo_PreLoadingPilotsCaching));
using (var ctx = new WWWingsContext())
{
// 1. Load ALL pilots
ctx.PilotSet.ToList();
// 2. Load only several flights. The Pilot and Copilot object will then be available for every flight!
var flightNoListe = new List <int>()
{
101, 117, 119, 118
};
foreach (var flightNo in flightNoListe)
{
var f = ctx.FlightSet
.SingleOrDefault(x => x.FlightNo == flightNo);
Console.WriteLine($"Flight Nr {f.FlightNo} from {f.Departure} to {f.Destination} has {f.FreeSeats} free seats!");
if (f.Pilot != null)
{
Console.WriteLine($"Pilot: {f.Pilot.Surname} has {f.Pilot.FlightAsPilotSet.Count} flights as pilot!");
}
else
{
Console.WriteLine("No pilot assigned!");
}
if (f.Copilot != null)
{
Console.WriteLine($"Copilot: {f.Copilot.Surname} has {f.Copilot.FlightAsCopilotSet.Count} flights as copilot!");
}
else
{
Console.WriteLine("No copilot assigned!");
}
}
}
}
public static void Demo1_PilotBleibtImRAM()
{
CUI.Headline("RelationshipFixup/First Level Cache");
int flightNo = 101;
int pilotID = 0;
// Vorspiel: passende PilotID ermittelt
using (var ctx = new WWWingsContext())
{
pilotID = ctx.FlightSet.Include(f => f.Pilot).SingleOrDefault(f => f.FlightNo == flightNo).PilotId;
}
using (var ctx = new WWWingsContext())
{
var pilot = ctx.PilotSet.AsNoTracking().SingleOrDefault(x => x.PersonID == pilotID);
Console.WriteLine("--- Navigationseigenschaften-Mengentypen");
Console.WriteLine(pilot.FlightAsPilotSet?.Count + " FlightAsPilotSet: " + pilot.FlightAsPilotSet?.GetType().FullName);
Console.WriteLine(pilot.FlightAsCopilotSet?.Count + " FlightAsCopilotSet: " + pilot.FlightAsCopilotSet?.GetType().FullName);
Console.WriteLine("Pilot: " + pilot);
pilot = null;
// der Pilot sollte nun weg sein
var flight = ctx.FlightSet.Include(f => f.Pilot).SingleOrDefault(f => f.FlightNo == flightNo);
Console.WriteLine(flight);
Console.WriteLine(flight.Pilot);
if (flight.Pilot != null)
{
CUI.PrintSuccess("Fixup OK!");
}
else
{
CUI.PrintError("Fixup geht nicht!");
}
}
}
public static void RemoveFlight()
{
CUI.MainHeadline(nameof(RemoveFlight));
using (WWWingsContext ctx = new WWWingsContext())
{
var f = ctx.FlightSet.SingleOrDefault(x => x.FlightNo == 123456);
if (f == null)
{
return;
}
Console.WriteLine($"After loading: Flight #{f.FlightNo}: {f.Departure}->{f.Destination} has {f.FreeSeats} free seats! State of the flight object: " + ctx.Entry(f).State);
// Remove flight
ctx.FlightSet.Remove(f);
// or: ctx.Remove(f);
Console.WriteLine($"After deleting: Flight #{f.FlightNo}: {f.Departure}->{f.Destination} has {f.FreeSeats} free seats! State of the flight object: " + ctx.Entry(f).State);
try
{
var anz = ctx.SaveChanges();
if (anz == 0)
{
Console.WriteLine("Problem: No changes saved!");
}
else
{
Console.WriteLine("Number of saved changes: " + anz);
}
Console.WriteLine($"After saving: Flight #{f.FlightNo}: {f.Departure}->{f.Destination} has {f.FreeSeats} free seats! State of the flight object: " + ctx.Entry(f).State);
}
catch (Exception ex)
{
Console.WriteLine("Error: " + ex.ToString());
}
}
}
public static void EF_ChangeTracking()
{
CUI.MainHeadline(nameof(EF_ChangeTracking));
using (WWWingsContext ctx = new WWWingsContext())
{
// kommt in nächster Version
//ctx.Configuration.AutoDetectChangesEnabled = false;
var f = ctx.FlightSet.FirstOrDefault();
Console.WriteLine("Before: " + f.ToString());
//Änderung
f.FreeSeats = (short)(new Random(DateTime.Now.Millisecond).Next(1, 100));
Console.WriteLine("After: " + f.ToString());
EFC_Util.PrintChangeInfo(ctx);
var anz = ctx.SaveChanges();
Console.WriteLine("Anzahl gespeicherter Ändeurngen: " + anz);
}
}
/// <summary>
/// Nur geänderte Spalten zurückschreiben
/// Attach()/IsModified=true
/// achtung: Geht nicht wenn Concurrency Check auf FreeSeats, da da EF den neuen Wert auch als alten Wert annimmt!
/// </summary>
public static void Detached_Flight_EinzelneProperties()
{
CUI.MainHeadline(nameof(Detached_Flight_EinzelneProperties));
Flight flight;
CUI.Print("Lade Objekt in Kontextinstanz #1");
using (WWWingsContext ctx1 = new WWWingsContext())
{
ctx1.Log();
//ctx1.Configuration.LazyLoadingEnabled = false;
flight = ctx1.FlightSet.Find(110);
}
CUI.Print("Objekt ändern");
CUI.Print(flight.ToString());
flight.Memo = "last changed at " + DateTime.Now;
flight.FreeSeats--;
CUI.Print(flight.ToString());
CUI.Print("Objekt nun speichern mit Kontextinstanz #2");
using (WWWingsContext ctx2 = new WWWingsContext())
{
ctx2.Log();
ctx2.FlightSet.Attach(flight);
CUI.Print(ctx2.Entry(flight).State.ToString());
// Zustand einzelner Properties ändern
ctx2.Entry(flight).Property(x => x.Memo).IsModified = true;
ctx2.Entry(flight).Property(x => x.FreeSeats).IsModified = true;
CUI.Print(ctx2.Entry(flight).State.ToString());
var count = ctx2.SaveChanges();
Console.WriteLine("Saved changes: " + count.ToString());
if (count != 1)
{
Debugger.Break();
}
}
}
public static void Demo_PreLoading1()
{
CUI.MainHeadline(nameof(Demo_PreLoading1));
var ctx = new WWWingsContext();
// Pre-Loading all pilots
var piotenSet = ctx.PilotSet.ToList();
Console.WriteLine("Anzahl Pilots: " + piotenSet.Count);
//ctx.PassengerSet.ToList();
// Now load some flights
var flightSet = ctx.FlightSet.Take(10).ToList();
var flight = flightSet.ElementAt(0);
Console.WriteLine(flight.ToString());
//Console.WriteLine("Number of passengers on this flight: " + flight.PassengerSet.Count);
if (flight.Pilot != null)
{
Console.WriteLine("Pilot: " + flight.Pilot.FullName);
}
else
{
Debugger.Break();
}
foreach (var f in flightSet.Take(10))
{
Console.WriteLine(f.ToString());
//Console.WriteLine("Number of passengers on this flight: " + f.PassengerSet.Count);
if (flight.Pilot != null)
{
Console.WriteLine("Pilot: " + f.Pilot.FullName);
}
}
}
