Adding/deleting from data tables
The data table must be marked as a Drupal Entity -- then the columns of the table may make use of the Field UI to allow an edit page per entry similar to a node_edit form.

Otherwise, you may be able to use the Editable Views module to make a table redition of your Data table -- whose cells are editable values. In this case you will likely still need to make the whole table a drupal entity.

The Data module is an API module to adopt/destroy SQL tables into Drupal. It's not really designed as a phpmyadmin replacement for a site.