在这种情况下，ASCII()函数的输出取决于我们是否将NULL作为字符串提供，还是仅仅提供NULL。以下示例将演示区别−
mysql> SELECT ASCII(null); +-------------+ | ASCII(null) | +-------------+ | NULL | +-------------+ 1 row in set (0.00 sec) mysql> SELECT ASCII('null'); +---------------+ | ASCII('null') | +---------------+ | 110 | +---------------+ 1 row in set (0.00 sec) mysql> Select ASCII(NULL); +-------------+ | ASCII(NULL) | +-------------+ | NULL | +-------------+ 1 row in set (0.00 sec) mysql> Select ASCII('NULL'); +---------------+ | ASCII('NULL') | +---------------+ | 78 | +---------------+ 1 row in set (0.00 sec)
As we can observe from the above result set that when we will provide NULL or null as a string, ASCII() function will return the number code of the first character i.e. number code of N in case of ‘NULL’ and number code of n in case of ‘null’, otherwise when we provide simply NULL then it returns NULL as output.
以上是如果我将NULL提供给MySQL的ASCII()函数，它会返回什么？的详细内容。更多信息请关注PHP中文网其他相关文章！
