mysql语句where条件中的~是什么意思

Question

SELECT aaa103, aaa102 FROM aa10 WHERE aaa100 = ~'AKC022~' 

Answer 1

我试了一下 ，这计算出来的值是相等的：mysql> select ~0;
+----------------------+
| ~0                   |
+----------------------+
| 18446744073709551615 |
+----------------------+
1 row in set (0.16 sec)mysql> select  ~'AKC022~';
+----------------------+
| ~'AKC022~'           |
+----------------------+
| 18446744073709551615 |
+----------------------+
1 row in set, 1 warning (0.00 sec)

Answer 2

其实就是，比如0，那么~0 =  18446744073709551615，那么这数字其实就是 二进制的 1111111111111111111111111111111111111111111111111111111111111111 ，共64位。mysql> select ~0;
+----------------------+
| ~0                   |
+----------------------+
| 18446744073709551615 |
+----------------------+
1 row in set (0.00 sec)mysql> select bin(0);
+--------+
| bin(0) |
+--------+
| 0      |
+--------+
1 row in set (0.00 sec)mysql> select bin(18446744073709551615);
+------------------------------------------------------------------+
| bin(18446744073709551615)                                        |
+------------------------------------------------------------------+
| 1111111111111111111111111111111111111111111111111111111111111111 |
+------------------------------------------------------------------+
1 row in set (0.01 sec)mysql>