Question

我有两个提交按钮，它们从两个表单中获取值并将它们插入数据库中。问题是我需要从第一个表（课程）中获取最后插入的id以插入第二个表（学生），但它不起作用。这就是我所做的：

<?php
$course_name = // the value of the field for the course name
$student_name = // The first name of the student
$student_age = // The age of the student
$last_id = // The last id of table courses
  if(isset($_POST['submit1'])){
          $query1 = "INSERT INTO courses (course_name)VALUES ('$course_name')";
                if ($object->query($query1) === true){
                    $last_id = LAST_INSERT_ID();
                    $good = "the course has been created";
                }
                else{
                    $bad = "Error: " .$query1.$object->error;
                }
    }

 if(isset($_POST['submit2'])){
          $query2 = "INSERT INTO students (course_id,student_name, student_age)VALUES ('last_id','$student_name','student_age')";
                if ($object->query($query2) === true){

                    $good = "the student has been created";
                }
                else{
                    $bad = "Error: " .$query2.$object->error;
                }
    }
?>

我不知道为什么它不起作用。

Answer 1

你没有提到你是否正在使用PDO或mysqli等等。如果它是mysqli它$mysqli->insert_id;

if ($object->query($query1) === true){
      $last_id = $object->insert_id
      $good = "the course has been created";
}

OTH，如果你使用的是PDO lastInsertId

if ($object->query($query1) === true){
      $last_id = $object->lastInsertId()
      $good = "the course has been created";
}

LAST_INSERT_ID不起作用

1 个答案: