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public void MyWhere()
{
NorthwindDataContext dc = new NorthwindDataContext();
//²éѯ²úÆ·Ãû³ÆÒÔL¿ªÍ·µÄ¼Ç¼
var query = from p in dc.Products
where p.ProductName.StartsWith("L")
select p;
//Á½¸öwhere¹ýÂËÁ½¸öÌõ¼þ£¬µÚ¶þ¸öwhere»áÔÚµÚÒ»¸öwhere»ù´¡ÉϽøÐеڶþ´ÎÌõ¼þν´Ê
var query1 = from p in dc.Products
where p.ProductName.StartsWith("L")
where p.ProductName.EndsWith("i")
select p;
foreach (Products item in query1)
{
Response.Write(item.ProductID + " | " + item.ProductName + "<br />");
}
}
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¿ÉÒÔ¿´µ½OrderÒÀÀµCustomer

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public void MyJoin()
{
// PERFORMING JOINS
NorthwindDataContext dc = new NorthwindDataContext();
dc.Log = Console.Out;
var query = from c in dc.Customers
join o in dc.Orders on c.CustomerID equals o.CustomerID
orderby c.CustomerID
select new
{
c.CustomerID,
c.CompanyName,
c.Country,
o.OrderID,
o.OrderDate
};
foreach (var item in query)
{
Response.Write(item


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id int identity(1,1) primary key not null,
name varchar(15)
);
insert into customers(name) values("name1"),("name2");
select id from customers;

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alter index &index_name monitoring usage;
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select * from v$object_usage where index_name =
&index_name;
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select
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