[Fact]
public void ShouldGetCarsOnOrderWithRelatedPropertiesAsSplitQuery()
{
IQueryable<Car> query = Context.Cars.Where(c => c.Orders.Any())
.Include(c => c.MakeNavigation)
.Include(c => c.Orders).ThenInclude(o => o.CustomerNavigation)
<b>.AsSplitQuery()</b>;
var cars = query.ToList();
Assert.Equal(4, cars.Count);
cars.ForEach(c =>
{
Assert.NotNull(c.MakeNavigation);
Assert.NotNull(c.Orders.ToList()[0].CustomerNavigation);
});
}
Метод ToQueryString() возвращает только первый запрос, поэтому последующие запросы были получены с применением профилировщика SQL Server:
SELECT [i].[Id], [i].[Color], [i].[IsDrivable], [i].[MakeId],
[i].[PetName], [i].[TimeStamp], [m].[Id], [m].[Name], [m].[TimeStamp]
FROM [dbo].[Inventory] AS [i]
INNER JOIN [dbo].[Makes] AS [m] ON [i].[MakeId] = [m].[Id]
WHERE ([i].[IsDrivable] = CAST(1 AS bit)) AND EXISTS (
SELECT 1
FROM [Dbo].[Orders] AS [o]
INNER JOIN (
SELECT [i0].[Id], [i0].[Color], [i0].[IsDrivable], [i0].[MakeId],
[i0].[PetName], [i0].[TimeStamp]
FROM [dbo].[Inventory] AS [i0]
WHERE [i0].[IsDrivable] = CAST(1 AS bit)
) AS [t] ON [o].[CarId] = [t].[Id]
WHERE ([t].[IsDrivable] = CAST(1 AS bit)) AND ([i].[Id] = [o].[CarId]))
ORDER BY [i].[Id], [m].[Id]
SELECT [t0].[Id], [t0].[CarId], [t0].[CustomerId], [t0].[TimeStamp],
[t0].[Id1], [t0].[TimeStamp1], [t0].[FirstName], [t0].[FullName],
[t0].[LastName], [i].[Id], [m].[Id]
FROM [dbo].[Inventory] AS [i]
INNER JOIN [dbo].[Makes] AS [m] ON [i].[MakeId] = [m].[Id]
INNER JOIN (
SELECT [o].[Id], [o].[CarId], [o].[CustomerId], [o].[TimeStamp],
[c].[Id] AS [Id1], [c].[TimeStamp] AS [TimeStamp1], [c].[FirstName],
[c].[FullName], [c].[LastName]
FROM [Dbo].[Orders] AS [o]
INNER JOIN (
SELECT [i0].[Id], [i0].[IsDrivable]
(window.adrunTag = window.adrunTag || []).push({v: 1, el: 'adrun-4-390', c: 4, b: 390})
FROM [dbo].[Inventory] AS [i0]
WHERE [i0].[IsDrivable] = CAST(1 AS bit)
) AS [t] ON [o].[CarId] = [t].[Id]
INNER JOIN [Dbo].[Customers] AS [c] ON [o].[CustomerId] = [c].[Id]
WHERE [t].[IsDrivable] = CAST(1 AS bit)
) AS [t0] ON [i].[Id] = [t0].[CarId]
WHERE ([i].[IsDrivable] = CAST(1 AS bit)) AND EXISTS (
SELECT 1
FROM [Dbo].[Orders] AS [o0]
INNER JOIN (
SELECT [i1].[Id], [i1].[Color], [i1].[IsDrivable], [i1].[MakeId],
[i1].[PetName], [i1].[TimeStamp]
FROM [dbo].[Inventory] AS [i1]
WHERE [i1].[IsDrivable] = CAST(1 AS bit)
) AS [t1] ON [o0].[CarId] = [t1].[Id]
WHERE ([t1].[IsDrivable] = CAST(1 AS bit)) AND ([i].[Id] = [o0].[CarId]))
ORDER BY [i].[Id], [m].[Id]
Будете вы разделять свои запросы или нет, зависит от существующих бизнес-требований.
Фильтрация связанных данных
В версии EF Core 5 появилась возможность фильтрации при включении навигационных свойств типа коллекций. До выхода EF Core 5 единственным способом получения отфильтрованного списка для навигационного свойства типа коллекций было использование явной загрузки. Добавьте в MakeTests.cs следующий тест, который демонстрирует получение записей производителей, выпускающих автомобили желтого цвета:
[Fact]
public void ShouldGetAllMakesAndCarsThatAreYellow()
{
var query = Context.Makes.IgnoreQueryFilters()
<b> .Include(x => x.Cars.Where(x => x.Color == "Yellow"));</b>
var qs = query.ToQueryString();
var makes = query.ToList();
Assert.NotNull(makes);
Assert.NotEmpty(makes);
Assert.NotEmpty(makes.Where(x => x.Cars.Any()));
Assert.Empty(makes.First(m => m.Id == 1).Cars);
Assert.Empty(makes.First(m => m.Id == 2).Cars);
Assert.Empty(makes.First(m => m.Id == 3).Cars);
Assert.Single(makes.First(m => m.Id == 4).Cars);
Assert.Empty(makes.First(m => m.Id == 5).Cars);
}
Ниже показан сгенерированный код SQL: