[phpmyadmin] This table does not contain a unique column. Grid edit, checkbox, Edit, Copy and Delete features are not available

Simply create a new column, set the Name to whatever you like, set the Type to INT and check the box that says A_I.

diagram The A_I checkbox stands for AUTO_INCREMENT, which essentially means that sequence numbers are assigned automatically in that new column (see below).

 column1 | column2 | id
-----------------------
 value   | value   | 1
-----------------------
 value   | value   | 2
-----------------------
 value   | value   | 3
-----------------------
 value   | value   | 4

This column essentially acts as a reference for phpMyAdmin to delete rows from. If necessary, click on the unique button for this new column, although this happened automatically for me. After following the above steps, you should no longer have the error message and buttons should appear for editing rows in phpMyAdmin!