Grouped selector can group text data from multiple elements into one record. The extracted data will be stored as JSON.
For example you are extracting a news article that might have multiple
reference links. If you are selecting these links with link selector with
multiple checked you would get duplicate articles in the result set where each
record would contain one reference link. Using grouped selector you could
serialize all these reference links into one record. To do that select all
reference links and set attribute name to
href to also extract links to these