쿼리 식 구문 예제: 분할(LINQ to Entities)
이 항목의 예제에서는 쿼리 식 구문을 사용하여 AdventureWorks Sales 모델을 쿼리하기 위해 Skip 및 Take 메서드를 사용하는 방법을 보여 줍니다. 이 예제에서 사용하는 AdventureWorks Sales 모델에서는 AdventureWorks 샘플 데이터베이스의 Contact, Address, Product, SalesOrderHeader 및 SalesOrderDetail 테이블을 사용합니다.
이 항목의 예제에서는 다음과 같은 using/Imports 문을 사용합니다.
Option Explicit On
Option Strict On
Imports L2EExamplesVB.AdventureWorksModel
Imports System.Data.Objects
Imports System.Globalization
using System;
using System.Data;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data.Objects;
using AdventureWorksModel;
using System.Globalization;
자세한 내용은 방법: Visual Studio에서 LINQ to Entities 프로젝트 만들기를 참조하십시오.
Skip
예제
다음 예제에서는 Skip 메서드를 사용하여 Seattle에 있는 처음 2개의 주소를 제외한 모든 주소를 가져옵니다.
Using AWEntities As New AdventureWorksEntities
Dim orders As ObjectQuery(Of SalesOrderHeader) = AWEntities.SalesOrderHeader
Dim addresses As ObjectQuery(Of Address) = AWEntities.Address
'LINQ to Entities only supports Skip on ordered collections.
Dim query = ( _
From address In addresses _
From order In orders _
Where address.AddressID = order.Address.AddressID _
And address.City = "Seattle" _
Order By order.SalesOrderID _
Select New With _
{ _
.City = address.City, _
.OrderID = order.SalesOrderID, _
.OrderDate = order.OrderDate _
}).Skip(2)
Console.WriteLine("All but first 2 orders in Seattle:")
For Each order In query
Console.WriteLine("City: {0} Order ID: {1} Total Due: {2:d}", _
order.City, order.OrderID, order.OrderDate)
Next
End Using
using (AdventureWorksEntities AWEntities = new AdventureWorksEntities())
{
ObjectQuery<Address> addresses = AWEntities.Address;
ObjectQuery<SalesOrderHeader> orders = AWEntities.SalesOrderHeader;
//LINQ to Entities only supports Skip on ordered collections.
var query = (
from address in addresses
from order in orders
where address.AddressID == order.Address.AddressID
&& address.City == "Seattle"
orderby order.SalesOrderID
select new
{
City = address.City,
OrderID = order.SalesOrderID,
OrderDate = order.OrderDate
}).Skip(2);
Console.WriteLine("All but first 2 orders in Seattle:");
foreach (var order in query)
{
Console.WriteLine("City: {0} Order ID: {1} Total Due: {2:d}",
order.City, order.OrderID, order.OrderDate);
}
Take
예제
다음 예제에서는 Take 메서드를 사용하여 Seattle에 있는 처음 3개의 주소를 가져옵니다.
Using AWEntities As New AdventureWorksEntities
Dim orders As ObjectQuery(Of SalesOrderHeader) = AWEntities.SalesOrderHeader
Dim addresses As ObjectQuery(Of Address) = AWEntities.Address
Dim query = ( _
From address In addresses _
From order In orders _
Where address.AddressID = order.Address.AddressID _
And address.City = "Seattle" _
Select New With _
{ _
.City = address.City, _
.OrderID = order.SalesOrderID, _
.OrderDate = order.OrderDate _
}).Take(3)
Console.WriteLine("First 3 orders in Seattle:")
For Each order In query
Console.WriteLine("City: {0} Order ID: {1} Total Due: {2:d}", _
order.City, order.OrderID, order.OrderDate)
Next
End Using
using (AdventureWorksEntities AWEntities = new AdventureWorksEntities())
{
ObjectQuery<Address> addresses = AWEntities.Address;
ObjectQuery<SalesOrderHeader> orders = AWEntities.SalesOrderHeader;
var query = (
from address in addresses
from order in orders
where address.AddressID == order.Address.AddressID
&& address.City == "Seattle"
select new
{
City = address.City,
OrderID = order.SalesOrderID,
OrderDate = order.OrderDate
}).Take(3);
Console.WriteLine("First 3 orders in Seattle:");
foreach (var order in query)
{
Console.WriteLine("City: {0} Order ID: {1} Total Due: {2:d}",
order.City, order.OrderID, order.OrderDate);
}
}