bin是一种特别的列类型,用于存储两种可能的值(对应的值为1与0)
mysql> select a from t1; #直接查,显示为空
+------+
| a |
+------+
| |
| |
+------+
2 rows in set (0.00 sec)
mysql> select bin(a),b from t1;#加上bin,可以显示
+--------+------+
| bin(a) | b |
+--------+------+
| 1 | -127 |
| 1 | 127 |
+--------+------+
2 rows in set (0.01 sec)
mysql>
来自 “ ITPUB博客 ” ,链接:https://blog.itpub.net/9240380/viewspace-665759/
,如需转载,请注明出处,否则将追究法律责任。