Você não precisa definir o comprimento de int. Remova o (10)
CREATE TABLE Orders (
order_id int NOT NULL,
order_date date NOT NULL,
total_value varchar(250) DEFAULT NULL,
order_status varchar(250) DEFAULT NULL,
payment_type_id int NOT NULL,
delivery_id int DEFAULT NULL,
store_id int NOT NULL,
staff_id int DEFAULT NULL,
client_id int NOT NULL,
sale_type_id int NOT NULL
);
SQL FIDDLE DEMO
