CREATE TABLE TicketPurchase
(
    TicketNum NUMBER(4,0),
    SellDateandTime DATE NOT NULL,
    FlightDateandTime DATE NOT NULL,
    FlightNum NUMBER(3,0) NOT NULL,
    LName VARCHAR2(100) NOT NULL,
    FName VARCHAR2(100) NOT NULL,
    MName VARCHAR2(100) ,
    PassportSeries VARCHAR2(2) NOT NULL,
    PassportNumber NUMBER(6,0) NOT NULL,
    TicketType VARCHAR2(20) NOT NULL,
    Price DECIMAL(10,2) NOT NULL,
  CHECK(FlightDateandTime  > SellDateandTime),

    CONSTRAINT FKFlightDateandTime
    FOREIGN KEY (FlightDateandTime)
    REFERENCES Departures(DateandTime),

    CONSTRAINT FKFlightNum
    FOREIGN KEY (FlightNum)
    REFERENCES Flights(FlightNum),

    CONSTRAINT PKTicketPurchase PRIMARY KEY (TicketNum)
);

...

CREATE SEQUENCE TicketNum START WITH 1 INCREMENT BY 1;

INSERT INTO TicketPurchase
VALUES
(
TicketNum.NEXTVAL,
to_timestamp('2011-02-13 15:45:00','YYYY-MM-DD HH24:MI:SS'),
to_timestamp('2011-06-13 15:18:00','YYYY-MM-DD HH24:MI:SS'),
1,
'John',
'Smith',
NULL,
'MH',
123456,
'Business class',
300.10,
);

Error at Command Line:25 COLUMN:5
Error report:
SQL Error: ORA-00936: missing expression
00936. 00000 -  "missing expression"
*Cause:
*Action: