SQL & PL/SQL

Hi,

I am getting "ORA-00906 missing left parenthesis" error while creating the foreign key on city_name column in the t_friends table.

1) Parent table:

create table t_city
(
city_name varchar2(60) primary key
)

2) child table:

create table t_friends
(
friend_name varchar2(30) not null,
city_name varchar2(60)
)

alter table t_friends add constraint city_cons foreign key city_name reference t_city(city_name);

Please can you tell me what is the mistake i am doing in the above syntex.

Thanks,
Aravindh K