title: How to call Function in cx_Oracle with COMPARISON_TYPE returnType and Boolean input?
body: <p>I am trying to call the <a href="https://docs.oracle.com/database/121/ARPLS/d_comparison.htm#ARPLS870" rel="nofollow noreferrer">COMPARE function</a> from the <a href="https://docs.oracle.com/database/121/ARPLS/d_comparison.htm#ARPLS868" rel="nofollow noreferrer">DBMS_COMPARISON package</a></p>
  
  <p>I first create my comparison by </p>
  
  <pre><code>import cx_Oracle
  
  host = host
  service_name = service_name
  port = port
  password = password
  username = username
  
  
  dsn = cx_Oracle.makedsn( host, port,
                           service_name=service_name )
  db = cx_Oracle.connect(username, password, dsn )
  
  keyword_parameters = {
          'comparison_name':'my_comparison',
          'schema_name':'my_schema',      
          'object_name':'table_name',
          'dblink_name':'db_link'
  }
  cur.callproc('DBMS_COMPARISON.CREATE_COMPARISON', keywordParameters = keyword_parameters)
  </code></pre>
  
  <p>Now I want to call the function <code>DBMS_COMPARISON.COMPARE</code></p>
  
  <pre><code>DBMS_COMPARISON.COMPARE(
     comparison_name  IN   VARCHAR2,
     scan_info        OUT  COMPARISON_TYPE,
     min_value        IN   VARCHAR2   DEFAULT NULL,
     max_value        IN   VARCHAR2   DEFAULT NULL,
     perform_row_dif  IN   BOOLEAN    DEFAULT FALSE)
  RETURN BOOLEAN;
  </code></pre>
  
  <p>I have tried</p>
  
  <pre><code>cur.callfunc('DBMS_COMPARISON.COMPARE', int,
               keywordParameters={'comparison_name':'my_comparison', 'scan_info':cur.var(int), 'perform_row_dif':'TRUE'})
  </code></pre>
  
  <p>Or some variant of.  I am having trouble understanding how to set the <code>returnType</code> specified in the callfunc and also how to set the required boolean value for the <code>DBMS_COMPARISON.COMPARE</code> function call</p>