/SQL/Sql make sure every user is unqiuew

Sql make sure every user is unqiuew

create table user(
    user_id  INT  auto_increment  PRIMARY KEY,
    username varchar(50) not null,
    avator  varchar(50),
    gender  boolean not null,
    phone varchar(20),
    unique(username)
);

create table journey(
    id INT auto_increment PRIMARY KEY,
    start varchar(100) not null,
    dest varchar(100) not null,
    time date not null,
    person INT,
    user_id INT not null,
    foreign key(user_id) references user(user_id)
);

Source: stackoverflow.com

Similar codes

0 vote119 views1 answer
USING THE NOT CONDITION IN SQL
SQL
0 vote113 views1 answer
Mysql show category once count how many products
SQL
0 vote71 views2 answers
Delete the last item in a table sql
SQL
0 vote129 views1 answer
Reset a table's identity column and remove test records
SQL
0 vote116 views2 answers
Mysql get routine parameter list
SQL
1 vote118 views1 answer
Sql server cast date dd/mm/yyyy
SQL
4 votes110 views1 answer
Force drop all tables postgres
SQL
1 vote117 views1 answer
Influxdb export to csv
SQL
2 votes122 views1 answer
Oracle to_char number format percentage
SQL
-1 vote123 views1 answer
How to change the auto increment in existing table mysql
SQL