title: How to solve SQL Error: ORA-01858 in oracle 11g
body: <p>I am trying to create a table with an existing DDL file, the statement is pretty much like this </p>
  
  <pre><code>CREATE TABLE SYSTEM.LS_Ss_VERSION 
      ( 
       ID NUMBER (20)  NOT NULL , 
       SSID NUMBER (20) , 
       CONTENT VARCHAR2 (4000 BYTE) , 
       CREATEDBY NUMBER (20) , 
       CREATED_ON DATE DEFAULT 'NULL' 
      ) 
  </code></pre>
  
  <p>The error am getting is </p>
  
  <pre><code>SQL Error: ORA-01858: a non-numeric character was found where a numeric was expected
  01858. 00000 -  "a non-numeric character was found where a numeric was expected"
  *Cause:    The input data to be converted using a date format model was
             incorrect.  The input data did not contain a number where a number was
             required by the format model.
  </code></pre>
  
  <p>I have searched google, but couldnt get proper solution.. Plese suggest me a solution here.</p>