create table Customer (
Id int identity,
FirstName nvarchar(40) not null,
LastName nvarchar(40) not null,
City nvarchar(40) null,
Country nvarchar(40) null,
Phone nvarchar(20) null,
constraint PK_CUSTOMER primary key (Id)
create table "Order" (
Id int identity,
OrderDate datetime not null default getdate(),
OrderNumber nvarchar(10) null,
CustomerId int not null,
TotalAmount decimal(12,2) null default 0,
constraint PK_ORDER primary key (Id)
)
create table OrderItem (
Id int identity,
OrderId int not null,
ProductId int not null,
UnitPrice decimal(12,2) not null default 0,
Quantity int not null default 1,
constraint PK_ORDERITEM primary key (Id)
create table Product (
Id int identity,
ProductName nvarchar(50) not null,
SupplierId int not null,
UnitPrice decimal(12,2) null default 0,
Package nvarchar(30) null,
IsDiscontinued bit not null default 0,
constraint PK_PRODUCT primary key (Id)
create table Supplier (
Id int identity,
CompanyName nvarchar(40) not null,
ContactName nvarchar(50) null,
ContactTitle nvarchar(40) null,
City nvarchar(40) null,
Country nvarchar(40) null,
Phone nvarchar(30) null,
Fax nvarchar(30) null,
constraint PK_SUPPLIER primary key (Id)
)
INSERT INTO [Customer] ([Id],[FirstName],[LastName],[City],[Country],[Phone])VALUES(6,'Hanna','Moos','Mannheim','Germany','0621-08460')
INSERT INTO [Customer] ([Id],[FirstName],[LastName],[City],[Country],[Phone])VALUES(7,'Frédérique','Citeaux','Strasbourg','France','88.60.15.31')
INSERT INTO [Customer] ([Id],[FirstName],[LastName],[City],[Country],[Phone])VALUES(8,'Martín','Sommer','Madrid','Spain','(91) 555 22 82')
INSERT INTO [Supplier] ([Id],[CompanyName],[ContactName],[City],[Country],[Phone],[Fax])VALUES(4,'Tokyo Traders','Yoshi Nagase','Tokyo','Japan','(03) 3555-5011',NULL)
INSERT INTO [Supplier] ([Id],[CompanyName],[ContactName],[City],[Country],[Phone],[Fax])VALUES(5,'Cooperativa de Quesos ''Las Cabras''','Antonio del Valle Saavedra','Oviedo','Spain','(98) 598 76 54',NULL)
INSERT INTO [Supplier] ([Id],[CompanyName],[ContactName],[City],[Country],[Phone],[Fax])VALUES(6,'Mayumi''s','Mayumi Ohno','Osaka','Japan','(06) 431-7877',NULL)
INSERT INTO [Product] ([Id],[ProductName],[SupplierId],[UnitPrice],[Package],[IsDiscontinued])VALUES(4,'Chef Anton''s Cajun Seasoning',2,22.00,'48 - 6 oz jars',0)
INSERT INTO [Product] ([Id],[ProductName],[SupplierId],[UnitPrice],[Package],[IsDiscontinued])VALUES(5,'Chef Anton''s Gumbo Mix',2,21.35,'36 boxes',1)
INSERT INTO [Product] ([Id],[ProductName],[SupplierId],[UnitPrice],[Package],[IsDiscontinued])VALUES(6,'Grandma''s Boysenberry Spread',3,25.00,'12 - 8 oz jars',0)
INSERT INTO [Order] ([Id],[OrderDate],[CustomerId],[TotalAmount],[OrderNumber])VALUES(5,'Jul 9 2012 12:00:00:000AM',76,3730.00,'542382')
INSERT INTO [Order] ([Id],[OrderDate],[CustomerId],[TotalAmount],[OrderNumber])VALUES(6,'Jul 10 2012 12:00:00:000AM',34,1444.80,'542383')
INSERT INTO [Order] ([Id],[OrderDate],[CustomerId],[TotalAmount],[OrderNumber])VALUES(7,'Jul 11 2012 12:00:00:000AM',14,625.20,'542384')
INSERT INTO [Order] ([Id],[OrderDate],[CustomerId],[TotalAmount],[OrderNumber])VALUES(8,'Jul 12 2012 12:00:00:000AM',68,2490.50,'542385')
INSERT INTO [OrderItem] ([Id],[OrderId],[ProductId],[UnitPrice],[Quantity])VALUES(4,2,14,18.60,9)
INSERT INTO [OrderItem] ([Id],[OrderId],[ProductId],[UnitPrice],[Quantity])VALUES(5,2,51,42.40,40)
INSERT INTO [OrderItem] ([Id],[OrderId],[ProductId],[UnitPrice],[Quantity])VALUES(6,3,41,7.70,10)
INSERT INTO [OrderItem] ([Id],[OrderId],[ProductId],[UnitPrice],[Quantity])VALUES(7,3,51,42.40,35)
INSERT INTO [OrderItem] ([Id],[OrderId],[ProductId],[UnitPrice],[Quantity])VALUES(8,3,65,16.80,15)
我需要协助回答以下问题：
a。每个供应商目前有多少种产品？注意：1 = 停产。
b。 2012、2013和2014年每月订单和收入是多少？结果应该在一张表中。
c。每个客户的总销售额和订单数是多少？