SQL & PL/SQL

hi guys ,,,

After greeting,,

I'm Ali new student in Oracle developer. I want to design airline reservation system by SQL*. Any Advice plz. I have already designed those table. if there is any comment plz correct me.

agent table
agent id (PK)
agent name
location(Aseeb, Ruwi)


ticket table
t_no
P_ID (FK)
agent id (FK)
F_no (FK)
seat no



Flight table
F_no (PK)
dep_city
arr_city
dep_time
arr_time
airport (FK)



passenger table
P_ID (PK)
F_name
S_name
L_name
DOB
Nationality
id type



airport table
airport_code (PK)
airport name
county