“wp_rg_form_view” refers to the form view database table used by Gravity Forms. The table is named using your site’s database prefix (“wp” is the default) plus “rg_form_view”.

Note: Once Gravity Forms version 2.3 is released, the table will have the new name “wp_gf_form_view”.

Further details for this table can be found viewing the Database Storage Structure Reference document for Gravity Forms version 2.3.