I read from W3school that this command
P_Id int FOREIGN KEY REFERENCES Persons(P_Id)
will work in PLSQL, when I tried this on Sql Developer then It was throwing an exception of
ORA-00907: missing right parenthesis
after this I replaced this command with following
P_Id int,
CONSTRAINT fk_PerOrders FOREIGN KEY (P_Id) REFERENCES Persons(P_Id)
and it worked, I want to ask whether the first command is not for oracle or is there something wrong with my oracle.