concat
%63%6F%6E%63%61%74
group_concat
%67%72%6F%75%70%5F%63%6F%6E%63%61%74
like
%6C%69%6B%65
union select
%75%6E%69%6F%6E%20%73%65%6C%65%63%74
from
%66%72%6F%6D
where
%77%68%65%72%65