Learn LINQ to SQL (iv): query syntax

Select

Description: Query the customer's company name, address information

Query syntax:

var 构建匿名类型1 = from c in ctx.Customers
select new
{
公司名 = c.CompanyName,
地址 = c.Address
};

Corresponding SQL:

SELECT [t0].[CompanyName], [t0].[Address]
FROM [dbo].[Customers] AS [t0]

Description: Query the employee's name and year of employment

Query syntax:

var 构建匿名类型2 = from emp in ctx.Employees
select new
{
姓名 = emp.LastName + emp.FirstName,
雇用年 = emp.HireDate.Value.Year
};

Corresponding SQL:

SELECT [t0].[LastName] + [t0].[FirstName] AS [value], DATEPART(Year, [t0].[HireDate]) AS [value2]
FROM [dbo].[Employees] AS [t0]

Description: Inquires the customer ID and contact information (position and contact person)

Query syntax:

var 构建匿名类型3 = from c in ctx.Customers
select new
{
ID = c.CustomerID,
联系信息 = new
{
职位 = c.ContactTitle,
联系人 = c.ContactName
}
};

Corresponding SQL:

SELECT [t0].[CustomerID], [t0].[ContactTitle], [t0].[ContactName]
FROM [dbo].[Customers] AS [t0]