三.各数据表配套的 SQL 语句
表一:
CREATE TABLE music_information (
music_number INT NOT NULL PRIMARY KEY,
music_name CHAR ( 20 ) NULL,
songer_information CHAR ( 40 ),
pop_music CHAR ( 20 ) NULL,
upload_music CHAR ( 20 ) NULL
)
表二:
CREATE TABLE enter_information (
user_name CHAR ( 10 ) NOT NULL,
Password INT NULL,
verification_code CHAR ( 4 ) NULL,
PRIMARY KEY ( user_name ))
表三:
CREATE TABLE music_type (
music_name CHAR ( 20 ) NOT NULL,
different_ages CHAR ( 20 ) NULL,
different_background CHAR ( 20 ) NULL,
different_emotional CHAR ( 20 ) NULL,
different_language CHAR ( 20 ) NULL,
PRIMARY KEY ( music_name ))
表四:
CREATE TABLE download_ways (
music_name CHAR ( 10 ) NOT NULL,
the_way CHAR ( 10 ) NULL,
download_date CHAR ( 10 ) NULL,
PRIMARY KEY ( music_name ))
表五:
CREATE TABLE user_information (
user_name CHAR ( 10 ) NOT NULL,
sex CHAR ( 10 ) NOT NULL,