title: SQL Error: ORA-01722: invalid number
body: <p>Here is my table.</p>
  
  <pre><code>CREATE TABLE SCHEDULE (
      SCHEDULE_ID INT                NOT NULL
      ,ARRV_TIME  INT                NOT NULL
      ,DEP_TIME   INT                NOT NULL
      ,BUS_TRANSFERS  VARCHAR2(40)   NOT NULL
      ,BUS_ID  NUMERIC               NOT NULL
      ,TRAVEL_DIRECTION  VARCHAR(10) NOT NULL
      ,WEEK_DAY  INTEGER             NOT NULL
  );
  </code></pre>
  
  <p>I run this insert statement</p>
  
  <pre><code>INSERT INTO SCHEDULE (SCHEDULE_ID, ARRV_TIME, DEP_TIME, BUS_TRANSFERS, BUS_ID, TRAVEL_DIRECTION, WEEK_DAY) 
  VALUES (SEQ_SCHEDULE.NEXTVAL,'10', '11', 'White Oak', '2', 'North', '4');
  </code></pre>
  
  <p>and I get this error message:</p>
  
  <blockquote>
    <p>Error starting at line : 1 in command - INSERT INTO SCHEDULE
    (SCHEDULE_ID, ARRV_TIME, DEP_TIME, BUS_TRANSFERS, BUS_ID,
    TRAVEL_DIRECTION, WEEK_DAY) VALUES (SEQ_SCHEDULE.NEXTVAL,'10', '11',
    'White Oak', '2', 'North', '4')</p>
    
    <p>Error report - SQL Error: ORA-01722: invalid number
    01722. 00000 -  "invalid number"
    *Cause:    The specified number was invalid.
    *Action:   Specify a valid number.</p>
  </blockquote>