Creating Table with CC Exp Date - Oracle PL SQL - oracle

Question

I'm trying to create a table with date constraint that will make the date value of MM/YY for credit card expiration date. When I try to create the below table I receive the error:
CONSTRAINT exp_check CHECK TO_CHAR(exp_date,'MM/YY'),
*
ERROR at line 19:
ORA-00906: missing left parenthesis
Create table Orders
(o_id int NOT NULL,
c_id int NOT NULL,
p_id int NOT NULL,
s_id int NOT NULL,
order_date date DEFAULT sysdate,
o_qty number NOT NULL,
order_total number NOT NULL,
card_type varchar2(50) NOT NULL,
cc_number varchar2(50) NOT NULL,
exp_date date NOT NULL,
shipping_date date,
shipping_status varchar2(50) DEFAULT 'Not Shipped Yet',
UNIQUE (o_ID, c_ID, p_ID),
CONSTRAINT order_ID PRIMARY KEY (O_ID),
CONSTRAINT fk_cust_id FOREIGN KEY (C_ID) REFERENCES customers(C_ID),
CONSTRAINT fk_ship_id FOREIGN KEY (S_ID) REFERENCES shipping(S_ID),
CONSTRAINT qty_check CHECK (o_qty >= 0),
CONSTRAINT exp_check CHECK TO_CHAR(exp_date,'MM/YY'),
CONSTRAINT s_check CHECK (shipping_status IN
('Not shipped yet', 'Shipped', 'Delivered'))
);
Once I'm able to create the table I will create a executed stored procedure that will execute the below:
SET SERVEROUTPUT ON;
DECLARE
i_result varchar2(100);
BEGIN
place_order(2200,1,'Regular','VISA','1111-1111-2222-3333',11/19,1040,i_result);
END;

Answer 1

A date always has a day. month, year, hour, minute, and second. You could store a date that is midnight on the first of the month and validate that the exp_date = trunc(exp_date, 'MM'). When you display the value to the user, you'd then use the to_char expression to display it in the format that you want.
Alternately, you could store a string in the format MM/YY and your check constraint could put various validations on that string (i.e. the first two characters are a number between 1 and 12, the fourth and fifth characters are a number between 15 and 25, etc.).

Answer 2

As others have said, a DATE value in Oracle always has the fields YEAR, MONTH, DAY, HOURS, MINUTES, and SECONDS. I think what you want to do here is to store the last day/hour/minute/second of the expiration date in your EXP_DATE column, e.g. if expiration shown on the card is '07/19' you'd want to store 31-JUL-2019 23:59:59, which is the last possible second that the card is valid, in the EXP_DATE field. Then when you want to display the expiration date in its usual MM/YY format you just have to format it with TO_CHAR, e.g. TO_CHAR(EXP_DATE, 'MM/YY').
Best of luck.