database - i am getting an error while running this sql statement using sql developer ,oracle -

create table ward ( wardnumber int not null primary key, type varchar(50), name varchar(50), numberofrooms int );  create table patient ( patientid int not null primary key, empssn int, category varchar(50), discount int, firstname varchar(50), lastname varchar(50), address varchar(50), city varchar(50), birthdate date, gender varchar(50), age date, cellnumber varchar(50), bednumber int, roomnumber int, wardnumber int , diseaseid int,  constraint fk_ward_number foreign key (wardnumber) references ward(wardnumber)on update cascade, constraint fk_disease_id foreign key (diseaseid) references disease(diseaseid) );  

i following error regarding contraint update cascade thingy , have tried lot dient fixed help

error @ command line : 19 column : 83 error report - sql error: ora-00905: missing keyword 00905. 00000 - "missing keyword"

i think there issue primary key.

the correct sentence is

create table table_name (   column1 datatype null/not null,   column2 datatype null/not null,   ...    constraint constraint_name primary key (column1, column2, ... column_n) );