/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 vote163 views4 answers
Mysql on kubernetes
SQL
1 vote176 views1 answer
SQL date part only of datetime
SQL
0 vote183 views2 answers
SQLSTATE[HY000]: General error: 3780 Referencing column 'role_id' and referenced column 'id' in foreign key constraint 'user_role_id foreign' are incompatible.
SQL
1 vote181 views1 answer
Oracle create index if not exists
SQL
1 vote164 views1 answer
Convert rows to string sql server
SQL
1 vote179 views1 answer
Sql server today minus n
SQL
2 votes216 views1 answer
Oracle trace session
SQL
0 vote163 views1 answer
Drop constraint in ms sql
SQL
7 votes159 views1 answer
Append column sql
SQL
0 vote172 views1 answer
Oracle archivemode
SQL