表user中username为主键，其他属性依赖于username，所以满足BC范式。

3.5    创建语句
创建album表：
CREATE TABLE [dbo].[album](
    [acode] [nvarchar](50) COLLATE Chinese_PRC_CI_AS NOT NULL,
    [aname] [nvarchar](50) COLLATE Chinese_PRC_CI_AS NOT NULL,
    [time] [nvarchar](50) COLLATE Chinese_PRC_CI_AS NULL,
    [cover] [image] NOT NULL,
 CONSTRAINT [PK_album_1] PRIMARY KEY CLUSTERED

创建group表：
CREATE TABLE [dbo].[group](
    [gname] [nvarchar](50) COLLATE Chinese_PRC_CI_AS NOT NULL,
    [gcode] [nvarchar](50) COLLATE Chinese_PRC_CI_AS NOT NULL,
 CONSTRAINT [PK_group_1] PRIMARY KEY CLUSTERED


创建song表：
CREATE TABLE [dbo].[song](
    [sname] [nvarchar](50) COLLATE Chinese_PRC_CI_AS NOT NULL,
    [track] [char](2) COLLATE Chinese_PRC_CI_AS NOT NULL,
    [arranger] [nvarchar](50) COLLATE Chinese_PRC_CI_AS NOT NULL,
    [lyric] [nvarchar](50) COLLATE Chinese_PRC_CI_AS NULL,
    [vocal] [nvarchar](50) COLLATE Chinese_PRC_CI_AS NULL,
    [oricode] [nvarchar](50) COLLATE Chinese_PRC_CI_AS NOT NULL,
    [style] [nvarchar](50) COLLATE Chinese_PRC_CI_AS NULL,
    [scode] [nvarchar](50) COLLATE Chinese_PRC_CI_AS NOT NULL,
    [adduser] [nvarchar](50) COLLATE Chinese_PRC_CI_AS NULL,
 CONSTRAINT [PK_song_1] PRIMARY KEY CLUSTERED
(
    [scode] ASC
)WITH (IGNORE_DUP_KEY = OFF) ON [PRIMARY]
) ON [PRIMARY]

GO
SET ANSI_PADDING OFF
GO
USE [touhou music]
GO
ALTER TABLE [dbo].[song]  WITH CHECK ADD  CONSTRAINT [FK_song_ori] FOREIGN KEY([oricode])
REFERENCES [dbo].[ori] ([oricode])


创建gas表：
CREATE TABLE [dbo].[gas](
    [gcode] [nvarchar](50) COLLATE Chinese_PRC_CI_AS NOT NULL,
    [acode] [nvarchar](50) COLLATE Chinese_PRC_CI_AS NOT NULL,
    [scode] [nvarchar](50) COLLATE Chinese_PRC_CI_AS NOT NULL,
 CONSTRAINT [PK_gas] PRIMARY KEY CLUSTERED
(
    [gcode] ASC,
    [acode] ASC,
    [scode] ASC
)WITH (IGNORE_DUP_KEY = OFF) ON [PRIMARY]
) ON [PRIMARY]

GO
USE [touhou music]
GO
ALTER TABLE [dbo].[gas]  WITH CHECK ADD  CONSTRAINT [FK_gas_album] FOREIGN KEY([acode])
REFERENCES [dbo].[album] ([acode])
GO
ALTER TABLE [dbo].[gas]  WITH CHECK ADD  CONSTRAINT [FK_gas_group] FOREIGN KEY([gcode])
REFERENCES [dbo].[group] ([gcode])
GO
ALTER TABLE [dbo].[gas]  WITH CHECK ADD  CONSTRAINT [FK_gas_song] FOREIGN KEY([scode])
REFERENCES [dbo].[song] ([scode])


创建ori表：
CREATE TABLE [dbo].[ori](
    [oricode] [nvarchar](50) COLLATE Chinese_PRC_CI_AS NOT NULL,
    [origin] [nvarchar](50) COLLATE Chinese_PRC_CI_AS NOT NULL,
 CONSTRAINT [PK_ori] PRIMARY KEY CLUSTERED
(
    [oricode] ASC
)WITH (IGNORE_DUP_KEY = OFF) ON [PRIMARY]
) ON [PRIMARY]


创建user表：
CREATE TABLE [dbo].[user](
    [username] [nvarchar](50) COLLATE Chinese_PRC_CI_AS NOT NULL,
    [password] [varchar](50) COLLATE Chinese_PRC_CI_AS NOT NULL,
    [autho] [char](1) COLLATE Chinese_PRC_CI_AS NOT NULL,
    [quest] [nvarchar](50) COLLATE Chinese_PRC_CI_AS NULL,
    [ans] [nvarchar](50) COLLATE Chinese_PRC_CI_AS NULL, C#在线音乐信息查询和管理系统设计(6):http://www.youerw.com/jisuanji/lunwen_8171.html