< /p>
The mobile passed in is also of string type! ! !
Your string query should be quoted, replace the three single quotes above with three double quotes, and then
b.username='%s'
< /p>
![[Web front-end] Node.js quick start](https://img.php.cn/upload/course/000/000/067/662b5d34ba7c0227.png)
Your string query should be quoted, replace the three single quotes above with three double quotes, and then