php - MySQL 在 PHPMyAdmin 中运行，但 var_dump 在 PHP 中返回 null

Question

我类似地编写了三个查询，它们都在 PHPMyAdmin 中运行良好，但只有两个在 PHP 中运行良好。我已经在这几个小时了。任何帮助，将不胜感激。

这是代码

//Get student ID
$id = 441;

//Get student name
$sql = "SELECT name FROM Student where id=$id";
$result=mysqli_query($connect, $sql);
$rows = $result->fetch_assoc();
$name = $rows['name'];

//get fees id
$sql1 = "SELECT fees_id FROM fees_info,Student where fees_info.student_id = Student.id and id=$id";
$result1=mysqli_query($connect, $sql1);
$rows1 = $result1->fetch_assoc();

// get statement info
$sql2="SELECT date,time,description,credit,debit,balance FROM finances WHERE fees_id = $fees_id";
$result2=mysqli_query($connect, $sql2);
$rows2= $results2->fetch_assoc();                
$date = $rows2['date'];
$time = $rows2['time'];
$description = $rows2['description'];
$credit = $rows2['credit'];
$debit = $rows2['debit'];
$balance = $rows2['balance']; 

通过获取语句信息，var dump 在结果上返回 null 并且 U 不明白为什么，因为前两个在连接到数据库的同一个文件中运行

标签： phpsql