title: Oracle pl/sql map with value is array
body: <p>I need create associative array where key is VARCHAR(20) and value is array of varchars.
  For example: </p>
  
  <pre><code>customer_by_locations: {
     "London": {
                 "John Doe", "Samantha Simpson", "Nicolas Darcula"
               },
     "Stambul": {
                 "Abdula Ibn Rahim", "Another Abdula"
               }
  }
  </code></pre>
  
  <p>I have created query:</p>
  
  <pre><code>declare 
    type customers is varray(10) of varchar2(20);
    type locations is table of customers index by varchar2(20);
  
    list_locations locations;
    list_customers varchar(20);
  begin
    list_locations('London') := ("John Doe", "Samantha Simpson", "Nicolas Darcula");
    list_locations('Stambul') := ("Abdula Ibn Rahim", "Another Abdula");
  
    for i in 1 .. list_locations loop
      DBMS_OUTPUT.PUT_LINE('Total ' || list_locations(i));   
      //Something do 
    end loop;  
  end; 
  </code></pre>
  
  <p>But I have error </p>
  
  <blockquote>
    <p>PLS-00382: expression is of wrong type</p>
  </blockquote>
  
  <p>Please, tell me, how i will declare array as value and assign values in it in oracle pl/sql.</p>