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Bu sayfaya erişim yetkilendirme gerektiriyor. Oturum açmayı veya dizinleri değiştirmeyi deneyebilirsiniz.
Bu sayfaya erişim yetkilendirme gerektiriyor. Dizinleri değiştirmeyi deneyebilirsiniz.
Bu konudaki örnekler, sorgu ifadesi söz dizimini kullanarak Average sorgulamak için Count, Max, Min, Sumve yöntemlerinin nasıl kullanılacağını gösterir. Bu örneklerde kullanılan AdventureWorks Satış Modeli, AdventureWorks örnek veritabanındaki Contact, Address, Product, SalesOrderHeader ve SalesOrderDetail tablolarından oluşturulur.
Bu konudaki örneklerde aşağıdaki using/Imports deyimleri kullanılır:
using System;
using System.Data;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data.Objects;
using System.Globalization;
using System.Data.EntityClient;
using System.Data.SqlClient;
using System.Data.Common;
Option Explicit On
Option Strict On
Imports System.Data.Objects
Imports System.Globalization
Ortalama
Örnek
Aşağıdaki örnek, her stilin ürünlerinin ortalama liste fiyatını bulmak için Average yöntemini kullanır.
using (AdventureWorksEntities context = new AdventureWorksEntities())
{
ObjectSet<Product> products = context.Products;
var query = from product in products
group product by product.Style into g
select new
{
Style = g.Key,
AverageListPrice =
g.Average(product => product.ListPrice)
};
foreach (var product in query)
{
Console.WriteLine($"Product style: {product.Style} Average list price: {product.AverageListPrice}");
}
}
Using context As New AdventureWorksEntities
Dim products As ObjectSet(Of Product) = context.Products
Dim query = _
From prod In products _
Let styl = prod.Style _
Group prod By styl Into g = Group _
Select New With _
{ _
.Style = styl, _
.AverageListPrice = g.Average(Function(p) p.ListPrice) _
}
For Each prod In query
Console.WriteLine("Product style: {0} Average list price: {1}", _
prod.Style, prod.AverageListPrice)
Next
End Using
Örnek
Aşağıdaki örnekte, her kişi kimliği için vadesi geçmiş ortalama toplamı almak için Average kullanılır.
using (AdventureWorksEntities context = new AdventureWorksEntities())
{
ObjectSet<SalesOrderHeader> orders = context.SalesOrderHeaders;
var query =
from order in orders
group order by order.Contact.ContactID into g
select new
{
Category = g.Key,
averageTotalDue = g.Average(order => order.TotalDue)
};
foreach (var order in query)
{
Console.WriteLine($"ContactID = {order.Category} \t Average TotalDue = {order.averageTotalDue}");
}
}
Using context As New AdventureWorksEntities
Dim orders As ObjectSet(Of SalesOrderHeader) = context.SalesOrderHeaders
Dim query = _
From ord In orders _
Let contID = ord.Contact.ContactID _
Group ord By contID Into g = Group _
Select New With _
{ _
.Category = contID, _
.averageTotalDue = _
g.Average(Function(ord) ord.TotalDue) _
}
For Each ord In query
Console.WriteLine("ContactID = {0} " & vbTab & _
" Average TotalDue = {1}", _
ord.Category, ord.averageTotalDue)
Next
End Using
Örnek
Aşağıdaki örnekte, her ilgili kişi için ortalama toplam borç olan siparişleri almak için Average kullanılır.
using (AdventureWorksEntities context = new AdventureWorksEntities())
{
ObjectSet<SalesOrderHeader> orders = context.SalesOrderHeaders;
var query =
from order in orders
group order by order.Contact.ContactID into g
let averageTotalDue = g.Average(order => order.TotalDue)
select new
{
Category = g.Key,
CheapestProducts =
g.Where(order => order.TotalDue == averageTotalDue)
};
foreach (var orderGroup in query)
{
Console.WriteLine($"ContactID: {orderGroup.Category}");
foreach (var order in orderGroup.CheapestProducts)
{
Console.WriteLine($"Average total due for SalesOrderID {order.SalesOrderID} is: {order.TotalDue}");
}
Console.Write("\n");
}
}
Using context As New AdventureWorksEntities
Dim orders As ObjectSet(Of SalesOrderHeader) = context.SalesOrderHeaders
Dim query = _
From ord In orders _
Let contID = ord.Contact.ContactID _
Group ord By contID Into g = Group _
Let averageTotalDue = g.Average(Function(ord) ord.TotalDue) _
Select New With _
{ _
.Category = contID, _
.CheapestProducts = _
g.Where(Function(ord) ord.TotalDue = averageTotalDue) _
}
For Each orderGroup In query
Console.WriteLine("ContactID: {0}", orderGroup.Category)
For Each ord In orderGroup.CheapestProducts
Console.WriteLine("Average total due for SalesOrderID {1} is: {0}", _
ord.TotalDue, ord.SalesOrderID)
Next
Console.Write(vbNewLine)
Next
End Using
Sayı
Örnek
Aşağıdaki örnek, kişi kimliklerinin listesini ve her birinin kaç siparişi olduğunu döndürmek için Count kullanır.
using (AdventureWorksEntities context = new AdventureWorksEntities())
{
ObjectSet<Contact> contacts = context.Contacts;
//Can't find field SalesOrderContact
var query =
from contact in contacts
select new
{
CustomerID = contact.ContactID,
OrderCount = contact.SalesOrderHeaders.Count()
};
foreach (var contact in query)
{
Console.WriteLine($"CustomerID = {contact.CustomerID} \t OrderCount = {contact.OrderCount}");
}
}
Using context As New AdventureWorksEntities
Dim contacts As ObjectSet(Of Contact) = context.Contacts
Dim query = _
From cont In contacts _
Select New With _
{ _
.CustomerID = cont.ContactID, _
.OrderCount = cont.SalesOrderHeaders.Count() _
}
For Each cont In query
Console.WriteLine("CustomerID = {0} OrderCount = {1}", _
cont.CustomerID, cont.OrderCount)
Next
End Using
Örnek
Aşağıdaki örnek, ürünleri renge göre gruplandırmıştır ve her renk grubundaki ürün sayısını döndürmek için Count kullanır.
using (AdventureWorksEntities context = new AdventureWorksEntities())
{
ObjectSet<Product> products = context.Products;
var query =
from product in products
group product by product.Color into g
select new { Color = g.Key, ProductCount = g.Count() };
foreach (var product in query)
{
Console.WriteLine($"Color = {product.Color} \t ProductCount = {product.ProductCount}");
}
}
Using context As New AdventureWorksEntities
Dim products As ObjectSet(Of Product) = context.Products
Dim query = _
From prod In products _
Let pc = prod.Color _
Group prod By pc Into g = Group _
Select New With {.Color = pc, .ProductCount = g.Count()}
For Each prod In query
Console.WriteLine("Color = {0} " & vbTab & " ProductCount = {1}", _
prod.Color, prod.ProductCount)
Next
End Using
Maks
Örnek
Aşağıdaki örnek, her bir kişi kimliği için en büyük toplam borcu almak amacıyla Max yöntemini kullanır.
using (AdventureWorksEntities context = new AdventureWorksEntities())
{
ObjectSet<SalesOrderHeader> orders = context.SalesOrderHeaders;
var query =
from order in orders
group order by order.Contact.ContactID into g
select new
{
Category = g.Key,
maxTotalDue =
g.Max(order => order.TotalDue)
};
foreach (var order in query)
{
Console.WriteLine($"ContactID = {order.Category} \t Maximum TotalDue = {order.maxTotalDue}");
}
}
Using context As New AdventureWorksEntities
Dim orders As ObjectSet(Of SalesOrderHeader) = context.SalesOrderHeaders
Dim query = _
From ord In orders _
Let contID = ord.Contact.ContactID _
Group ord By contID Into g = Group _
Select New With _
{ _
.Category = contID, _
.MaxTotalDue = _
g.Max(Function(ord) ord.TotalDue) _
}
For Each ord In query
Console.WriteLine("ContactID = {0} " & vbTab & _
" Maximum TotalDue = {1}", _
ord.Category, ord.MaxTotalDue)
Next
End Using
Örnek
Aşağıdaki örnekte, her kişi kimliği için en yüksek toplam borcu olan siparişleri elde etmek için Max yöntemi kullanılmaktadır.
using (AdventureWorksEntities context = new AdventureWorksEntities())
{
ObjectSet<SalesOrderHeader> orders = context.SalesOrderHeaders;
var query =
from order in orders
group order by order.Contact.ContactID into g
let maxTotalDue = g.Max(order => order.TotalDue)
select new
{
Category = g.Key,
CheapestProducts =
g.Where(order => order.TotalDue == maxTotalDue)
};
foreach (var orderGroup in query)
{
Console.WriteLine($"ContactID: {orderGroup.Category}");
foreach (var order in orderGroup.CheapestProducts)
{
Console.WriteLine($"MaxTotalDue {order.TotalDue} for SalesOrderID {order.SalesOrderID}: ");
}
Console.Write("\n");
}
}
Using context As New AdventureWorksEntities
Dim orders As ObjectSet(Of SalesOrderHeader) = context.SalesOrderHeaders
Dim query = _
From ord In orders _
Let contID = ord.Contact.ContactID _
Group ord By contID Into g = Group _
Let maxTotalDue = g.Max(Function(ord) ord.TotalDue) _
Select New With _
{ _
.Category = contID, _
.CheapestProducts = _
g.Where(Function(ord) ord.TotalDue = maxTotalDue) _
}
For Each orderGroup In query
Console.WriteLine("ContactID: {0}", orderGroup.Category)
For Each ord In orderGroup.CheapestProducts
Console.WriteLine("MaxTotalDue {0} for SalesOrderID {1}: ", _
ord.TotalDue, ord.SalesOrderID)
Next
Console.Write(vbNewLine)
Next
End Using
Dakika
Örnek
Aşağıdaki örnek, her kişi kimliği için en küçük borç toplamını almak için Min yöntemini kullanır.
using (AdventureWorksEntities context = new AdventureWorksEntities())
{
ObjectSet<SalesOrderHeader> orders = context.SalesOrderHeaders;
var query =
from order in orders
group order by order.Contact.ContactID into g
select new
{
Category = g.Key,
smallestTotalDue =
g.Min(order => order.TotalDue)
};
foreach (var order in query)
{
Console.WriteLine($"ContactID = {order.Category} \t Minimum TotalDue = {order.smallestTotalDue}");
}
}
Using context As New AdventureWorksEntities
Dim orders As ObjectSet(Of SalesOrderHeader) = context.SalesOrderHeaders
Dim query = _
From ord In orders _
Let contID = ord.Contact.ContactID _
Group ord By contID Into g = Group _
Select New With _
{ _
.Category = contID, _
.smallestTotalDue = _
g.Min(Function(o) o.TotalDue) _
}
For Each ord In query
Console.WriteLine("ContactID = {0} " & vbTab & _
" Minimum TotalDue = {1}", ord.Category, ord.smallestTotalDue)
Next
End Using
Örnek
Aşağıdaki örnekte Min yöntemi, her iletişim için toplamı en küçük olan siparişleri almak için kullanılır.
using (AdventureWorksEntities context = new AdventureWorksEntities())
{
ObjectSet<SalesOrderHeader> orders = context.SalesOrderHeaders;
var query =
from order in orders
group order by order.Contact.ContactID into g
let minTotalDue = g.Min(order => order.TotalDue)
select new
{
Category = g.Key,
smallestTotalDue =
g.Where(order => order.TotalDue == minTotalDue)
};
foreach (var orderGroup in query)
{
Console.WriteLine($"ContactID: {orderGroup.Category}");
foreach (var order in orderGroup.smallestTotalDue)
{
Console.WriteLine($"Minimum TotalDue {order.TotalDue} for SalesOrderID {order.SalesOrderID}: ");
}
Console.Write("\n");
}
}
Using context As New AdventureWorksEntities
Dim orders As ObjectSet(Of SalesOrderHeader) = context.SalesOrderHeaders
Dim query = _
From ord In orders _
Let contID = ord.Contact.ContactID _
Group ord By contID Into g = Group _
Let minTotalDue = g.Min(Function(o) o.TotalDue) _
Select New With _
{ _
.Category = contID, _
.smallestTotalDue = _
g.Where(Function(o) o.TotalDue = minTotalDue) _
}
For Each orderGroup In query
Console.WriteLine("ContactID: {0}", orderGroup.Category)
For Each ord In orderGroup.smallestTotalDue
Console.WriteLine("Minimum TotalDue {0} for SalesOrderID {1}: ", _
ord.TotalDue, ord.SalesOrderID)
Next
Console.Write(vbNewLine)
Next
End Using
Toplam
Örnek
Aşağıdaki örnek, her kişi ID'si için ödenecek toplamı elde etmek amacıyla Sum yöntemini kullanır.
using (AdventureWorksEntities context = new AdventureWorksEntities())
{
ObjectSet<SalesOrderHeader> orders = context.SalesOrderHeaders;
var query =
from order in orders
group order by order.Contact.ContactID into g
select new
{
Category = g.Key,
TotalDue = g.Sum(order => order.TotalDue)
};
foreach (var order in query)
{
Console.WriteLine($"ContactID = {order.Category} \t TotalDue sum = {order.TotalDue}");
}
}
Using context As New AdventureWorksEntities
Dim orders As ObjectSet(Of SalesOrderHeader) = context.SalesOrderHeaders
Dim query = _
From ord In orders _
Let contID = ord.Contact.ContactID _
Group ord By contID Into g = Group _
Select New With _
{ _
.Category = contID, _
.TotalDue = g.Sum(Function(o) o.TotalDue) _
}
For Each ord In query
Console.WriteLine("ContactID = {0} " & vbTab & _
" TotalDue sum = {1}", ord.Category, ord.TotalDue)
Next
End Using