title: SQL Error: ORA-00922: missing or invalid option
body: <pre><code>CREATE TABLE chartered flight(flight_no NUMBER(4) PRIMARY KEY
  , customer_id NUMBER(6) REFERENCES customer(customer_id)
  , aircraft_no NUMBER(4) REFERENCES aircraft(aircraft_no)
  , flight_type VARCHAR2 (12)
  , flight_date DATE NOT NULL
  , flight_time INTERVAL DAY TO SECOND NOT NULL
  , takeoff_at CHAR (3) NOT NULL
  , destination CHAR (3) NOT NULL)
  </code></pre>
  
  <p>Should I not use CHAR data type? </p>
  
  <p>I hear it is bad practice to use it but I wanted to make it so takeoff_at and destination have to have minimum 3 characters because they are airport codes.  </p>
  
  <p>This is the error I am getting:</p>
  
  <pre><code>Error at Command Line:1 Column:23
  Error report:
  SQL Error: ORA-00922: missing or invalid option
  00922. 00000 -  "missing or invalid option"
  *Cause:    
  *Action:
  </code></pre>