Beispielcode zum Abfragen ungerader und gerader Zahlen mit MySQL

mysql> select * from forum_dummy where id&1 ;
+----+-----------+------------+
| id | user_name | dummy_name |
+----+-----------+------------+
|  1 | yang      | ting       |
|  3 | yang3     | ting3      |
+----+-----------+------------+
2 rows in set (0.00 sec)

mysql> select * from forum_dummy where id=(id>>1)<<1 ;
+----+-----------+------------+
| id | user_name | dummy_name |
+----+-----------+------------+
|  2 | yang1     | ting1      |
|  4 | yang4     | ting4      |
+----+-----------+------------+
2 rows in set (0.00 sec)

mysql> select conv(101010,2,10);
+-------------------+
| conv(101010,2,10) |
+-------------------+
| 42                |
+-------------------+
1 row in set (0.00 sec)
2）十进制--》十六进制
引用
mysql> select conv(999,10,16);
+-----------------+
| conv(999,10,16) |
+-----------------+
| 3E7             |
+-----------------+
1 row in set (0.00 sec)