title: RobotFramework DatabaseError: ORA-00911: invalid character
body: <p>Hi I am currently doing an automation testing script. And I have a portion where I would like to extract the data from the database and input them in text-fields. </p>
  
  <p>This is how I have written my codes:</p>
  
  <pre><code>Retrieve and Input
  Connect To Database Using Custom Params    cx_Oracle    '${Database Username}/${Database Password}@${Database Host}:${Database Port}/${DatabaseName}'
  ${ETD_Day}=      Execute Sql String      SELECT EXTRACT(DAY FROM 'DECL_UNBTHG_DT') FROM BAS_BERTH_APPLN_MASTER WHERE ABBR_VSL_M='APL';
  Input Text      ${FlexiStack_Day}       ${ETD_Day}
  Disconnect From Database
  </code></pre>
  
  <p>However when I am running for testing, this error showed up when trying to execute the sql string.</p>
  
  <blockquote>
    <p>DatabaseError: ORA-00911: invalid character</p>
  </blockquote>
  
  <p>I have tried to run the SQL statement in SQL developer and it works. May I know what is the issue here?</p>