title: How to check Parameter List value in Oracle PL/SQL?
body: <p>I created a param list and add some parameter, but when I want to check if the parameter and its value has been added, it cannot get the value I just added. What's wrong with the code : </p>
  
  <pre><code>IF NOT ID_NULL(GET_PARAMETER_LIST('RPT')) THEN
    DESTROY_PARAMETER_LIST('RPT');
  END IF;
  v_param_list := CREATE_PARAMETER_LIST('RPT');
  
  ADD_PARAMETER(v_param_list,'PAR_WHERE',TEXT_PARAMETER,'WHERE ID = 1010');
  
  BEGIN
     GET_PARAMETER_ATTR(v_param_list,'PAR_WHERE',v_param_type,v_temp);
     message('PAR_WHERE:'||v_temp);
  EXCEPTION WHEN OTHERS THEN
     message('Couldn''t get the value for : PAR_WHERE');
  END; 
  </code></pre>
  
  <p>How could I retrieve all the parameters and values in a param list ? </p>