public static void EFPlus_FutureQuery()
{
CUI.MainHeadline(nameof(EFPlus_FutureQuery));
using (var ctx = new DA.WWWingsContext())
{
ctx.Log();
CUI.Headline("Define three future queries ... nothing happens in the database");
QueryFutureEnumerable <Pilot> qAllePilots = ctx.PilotSet.Future();
QueryFutureEnumerable <Flight> qflightSetRome = ctx.FlightSet.Where(x => x.Departure == "Rome").Future();
QueryFutureEnumerable <Flight> qFlightSetBerlin = ctx.FlightSet.Where(x => x.Departure == "Berlin").Future();
CUI.Headline("Access the pilots:");
var allePilots = qAllePilots.ToList();
Console.WriteLine(allePilots.Count + " Pilots are loaded!");
CUI.Headline("Access the flights from Rome:");
var flightSetRom = qflightSetRome.ToList();
Console.WriteLine(flightSetRom.Count + " flights from Berlin are loaded!");
CUI.Headline("Define another two future queries ... nothing happens in the database");
QueryFutureEnumerable <Flight> qFugSetLondon = ctx.FlightSet.Where(x => x.Departure == "London").Future();
QueryFutureEnumerable <Flight> qflightSetParis = ctx.FlightSet.Where(x => x.Departure == "Paris").Future();
CUI.Headline("Access the flights from Berlin:");
var flightSetBerlin = qFlightSetBerlin.ToList();
Console.WriteLine(flightSetBerlin.Count + " flights from Rome are loaded!");
CUI.Headline("Access the flights from London:");
var flightSetLondon = qFugSetLondon.ToList();
Console.WriteLine(flightSetLondon.Count + " flights from London are loaded!");
CUI.Headline("Access the flights from Paris:");
var flightSetParis = qflightSetParis.ToList();
Console.WriteLine(flightSetParis.Count + " flights from Paris are loaded!");
}
}
public static async Task <T> SingleOrDefaultAsync <T>(this QueryFutureEnumerable <T> source)
{
if (!source.HasValue)
{
await source.OwnerBatch.ExecuteQueriesAsync().ConfigureAwait(false);
}
using (var enumerator = source.GetEnumerator())
{
if (!enumerator.MoveNext())
{
return(default(T));
}
var current = enumerator.Current;
if (!enumerator.MoveNext())
{
return(current);
}
}
throw new InvalidOperationException("Sequence contains more than one element");
}
public async Task <IActionResult> IndexAsync(CancellationToken cancellationToken = default)
{
await Context.Database.EnsureCreatedAsync(cancellationToken);
await Context.GenerateDataAsync(cancellationToken);
int count = await Context.Customers.AsNoTracking().CountAsync(cancellationToken);
int futureCount = Context.Customers.AsNoTracking().Future().Count();
_logger.LogInformation($"Future Customer Count: {futureCount}");
QueryFutureValue <int> futureMaxPrice =
Context.Products.AsNoTracking().DeferredMax(x => x.Prices).FutureValue <int>();
QueryFutureValue <int> futureMinPrice =
Context.Products.AsNoTracking().DeferredMin(x => x.Prices).FutureValue <int>();
int maxPrice = futureMaxPrice.Value;
int minPrice = futureMinPrice.Value;
_logger.LogInformation($"Max Price: {maxPrice}");
_logger.LogInformation($"Min Price: {minPrice}");
IEnumerable <Product> resultPeopleActive =
await Context.Products.AsNoTracking()
.Where(c => c.IsActive)
.ToListAsync(cancellationToken)
;
IEnumerable <Product> resultPeopleNonActive =
await Context.Products.AsNoTracking()
.Where(c => !c.IsActive)
.ToListAsync(cancellationToken)
;
QueryFutureEnumerable <Product> resultPeopleActiveWithFuture =
Context.Products.AsNoTracking()
.Where(c => c.IsActive)
.Future()
;
QueryFutureEnumerable <Product> resultPeopleNonActiveWithFuture =
Context.Products.AsNoTracking()
.Where(c => !c.IsActive)
.Future()
;
IEnumerable <Product> resultPeopleActiveWith =
await resultPeopleActiveWithFuture.ToListAsync(cancellationToken);
IEnumerable <Product> resultPeopleNonActiveWith =
await resultPeopleNonActiveWithFuture.ToListAsync(cancellationToken);
if (resultPeopleActive == resultPeopleActiveWith &&
resultPeopleNonActive == resultPeopleNonActiveWith)
{
_logger.LogInformation("Results are the same .. !!!!");
}
IQueryable <Product> query = Context.Products.AsNoTracking().Where(c => c.IsActive);
var pagedQueryable = await query
.OrderBy(p => p.ProductId)
.Skip(1).Take(4)
.Select(p => new
{
TotalAsync = query.CountAsync(cancellationToken),
Item = p
})
.ToListAsync(cancellationToken)
;
int totalQuery = await pagedQueryable.FirstOrDefault().TotalAsync;
IEnumerable <Product> items = pagedQueryable.Select(p => p.Item).ToList();
var page = await query
.OrderBy(p => p.Name)
.Select(p => p)
.Skip(1).Take(4)
.GroupBy(p => new { TotalAsync = query.CountAsync(cancellationToken) })
.FirstOrDefaultAsync(cancellationToken)
;
int total = await page.Key.TotalAsync;
IEnumerable <Product> people = page.Select(p => p);
IEnumerable <ProductResult> results = await query
.OrderBy(p => p.Name)
.Skip(1).Take(4)
.Select(p => new ProductResult(p, query.Count()))
.ToListAsync(cancellationToken)
;
int totalCount = results.FirstOrDefault().TotalCount;
IEnumerable <ProductResult> peopleResult = results.Select(p => p).ToList();
IQueryable <Product> queryAsQueryable = Context.Products.AsNoTracking().AsQueryable();
Task <List <Product> > resultsTask =
query.OrderBy(p => p.ProductId).Skip(1).Take(4).ToListAsync(cancellationToken);
Task <int> countTask = query.CountAsync(cancellationToken);
await Task.WhenAll(resultsTask, countTask);
int TotaslCount = await countTask;
IEnumerable <Product> Data = await resultsTask;
IQueryable <Customer> baseQuery = Context.Customers.Where(c => c.IsActive);
QueryFutureEnumerable <Customer> getTotalCountFuture = baseQuery.Future();
QueryFutureEnumerable <Customer> getPageFuture = baseQuery.Skip(1).Take(4).Future();
int getTotalCountResult = getTotalCountFuture.Count();
IEnumerable <Customer> getPageResult = await getPageFuture.ToListAsync(cancellationToken);
return(View());
}
public async Task <IActionResult> IndexAsync(CancellationToken cancellationToken = default)
{
await Context.Database.EnsureCreatedAsync(cancellationToken);
await Context.GenerateDataAsync(cancellationToken);
int count = await Context.Customers.CountAsync(cancellationToken);
int futureCount = Context.Customers.Future().Count();
Console.WriteLine("Future Customer Count: {0}", futureCount);
QueryFutureValue <int> futureMaxPrice =
Context.Products.DeferredMax(x => x.Prices).FutureValue <int>();
QueryFutureValue <int> futureMinPrice =
Context.Products.DeferredMin(x => x.Prices).FutureValue <int>();
int maxPrice = futureMaxPrice.Value;
int minPrice = futureMinPrice.Value;
Console.WriteLine("Max Price: {0}", maxPrice);
Console.WriteLine("Min Price: {0}", minPrice);
IEnumerable <Product> resultPeopleActive =
await Context.Products.AsNoTracking()
.Where(c => c.IsActive)
.ToListAsync(cancellationToken)
;
IEnumerable <Product> resultPeopleNonActive =
await Context.Products.AsNoTracking()
.Where(c => !c.IsActive)
.ToListAsync(cancellationToken)
;
IEnumerable <Product> resultPeopleActiveWithFuture =
await Context.Products.AsNoTracking()
.Where(c => c.IsActive)
.Future().ToListAsync(cancellationToken)
;
IEnumerable <Product> resultPeopleNonActiveWithFuture =
await Context.Products.AsNoTracking()
.Where(c => !c.IsActive)
.Future().ToListAsync(cancellationToken)
;
if (resultPeopleActive == resultPeopleActiveWithFuture &&
resultPeopleNonActive == resultPeopleNonActiveWithFuture)
{
Console.WriteLine("Results are the same .. !!!!");
}
IQueryable <Customer> baseQuery = Context.Customers.Where(c => c.IsActive);
QueryFutureEnumerable <Customer> getTotalCountFuture = baseQuery.Future();
QueryFutureEnumerable <Customer> getPageFuture = baseQuery.Skip(1).Take(4).Future();
int getTotalCountResult = getTotalCountFuture.Count();
IEnumerable <Customer> getPageResult = await getPageFuture.ToListAsync(cancellationToken);
return(View());
}
public async Task <IActionResult> IndexAsync(CancellationToken cancellationToken = default)
{
await Context.Database.EnsureCreatedAsync(cancellationToken);
await Context.GenerateDataAsync(cancellationToken);
int count = await Context.Customers.CountAsync(cancellationToken);
int futureCount = Context.Customers.Future().Count();
_logger.LogInformation($"Future Customer Count: {futureCount}");
QueryFutureValue <int> futureMaxPrice =
Context.Products.DeferredMax(x => x.Prices).FutureValue <int>();
QueryFutureValue <int> futureMinPrice =
Context.Products.DeferredMin(x => x.Prices).FutureValue <int>();
int maxPrice = futureMaxPrice.Value;
int minPrice = futureMinPrice.Value;
_logger.LogInformation($"Max Price: {maxPrice}");
_logger.LogInformation($"Min Price: {minPrice}");
IEnumerable <Product> resultPeopleActive =
await Context.Products.AsNoTracking()
.Where(c => c.IsActive)
.ToListAsync(cancellationToken)
;
IEnumerable <Product> resultPeopleNonActive =
await Context.Products.AsNoTracking()
.Where(c => !c.IsActive)
.ToListAsync(cancellationToken)
;
QueryFutureEnumerable <Product> resultPeopleActiveWithFuture =
Context.Products.AsNoTracking()
.Where(c => c.IsActive)
.Future()
;
QueryFutureEnumerable <Product> resultPeopleNonActiveWithFuture =
Context.Products.AsNoTracking()
.Where(c => !c.IsActive)
.Future()
;
IEnumerable <Product> resultPeopleActiveWith =
await resultPeopleActiveWithFuture.ToListAsync(cancellationToken);
IEnumerable <Product> resultPeopleNonActiveWith =
await resultPeopleNonActiveWithFuture.ToListAsync(cancellationToken);
if (resultPeopleActive == resultPeopleActiveWith &&
resultPeopleNonActive == resultPeopleNonActiveWith)
{
_logger.LogInformation("Results are the same .. !!!!");
}
IQueryable <Product> query = Context.Products.Where(c => c.IsActive);
var page = await query
.OrderBy(p => p.Name)
.Skip(1).Take(4)
.GroupBy(p => new { Total = query.Count() })
.FirstOrDefaultAsync(cancellationToken);
int total = page.Key.Total;
IEnumerable <Product> people = page.Select(p => p);
var results = query
.OrderBy(p => p.Name)
.Select(p => new
{
Product = p,
TotalCount = query.Count()
})
.Skip(1).Take(4)
.ToArray();
var totalCount = results.First().TotalCount;
var people = results.Select(r => r.Person).ToArray();
IQueryable <Customer> baseQuery = Context.Customers.Where(c => c.IsActive);
QueryFutureEnumerable <Customer> getTotalCountFuture = baseQuery.Future();
QueryFutureEnumerable <Customer> getPageFuture = baseQuery.Skip(1).Take(4).Future();
int getTotalCountResult = getTotalCountFuture.Count();
IEnumerable <Customer> getPageResult = await getPageFuture.ToListAsync(cancellationToken);
return(View());
}
public static Task <T> ValueAsync <T>(this QueryFutureEnumerable <T> source) where T : struct
{
return(source.SingleOrDefaultAsync());
}