MAKE_SET(bits,str1,str2,...)

返回一个设定值(含子字符串分隔字符串。，。字符)由那些在设置位的相应位的字符串。str1对应于位0，str2至位1，以此类推。NULL值在str1，str2，...不添加到结果。

SQL> SELECT MAKE_SET(1,'a','b','c');
+---------------------------------------------------------+
| MAKE_SET(1,'a','b','c')                                 |
+---------------------------------------------------------+
| a                                                       |
+---------------------------------------------------------+
1 row in set (0.00 sec)