How do I solve phpMyAdmin warnings saying “a form on this page has more than 5000 fields”?

If you use phpMyAdmin and view a table with a large number of columns, you may see a warning message saying:

Warning: a form on this page has more than 5000 fields. On submission, some of the fields might be ignored, due to PHP's max_input_vars configuration.

To avoid this problem, simply choose a smaller number of rows to view from the top of the page:

phpMyAdmin rows