code: private boolean isRestrictedByMultipleContains(ColumnDefinition columnDef)
      {
          if (!columnDef.type.isCollection())
              return false;
  
          Restriction restriction = metadataRestrictions.get(columnDef.name);
  
          if (!(restriction instanceof Contains))
              return false;
  
          Contains contains = (Contains) restriction;
          return (contains.numberOfValues() + contains.numberOfKeys()) > 1;
      }
docs: Checks if the specified column is restricted by multiple contains or contains key.
  
  @param columnDef the definition of the column to check
  @return <code>true</code> the specified column is restricted by multiple contains or contains key,
  <code>false</code> otherwise