Question

使用命令行迁移时，我收到此错误...

(errno: 150 "Foreign key con straint is incorrectly formed")

这是我的迁移代码..

public function up()
{
    Schema::enableForeignKeyConstraints();
    Schema::create('student', function (Blueprint $table) {
        $table->integer('student_id')->unsigned()->primary();
        $table->string('student_name', 200);
        $table->string('student_email', 50);
        $table->integer('class_id')->unsigned()->nullable();
        $table->string('password', 100);
        $table->rememberToken();
        $table->timestamps();
    });

    Schema::table('student', function($table) {
       $table->foreign('class_id')->references('class_id')->on('class_tbl');
    });
}

我还没有找到解决方法，我无法弄清楚出了什么问题......

编辑：

以下是class_tbl的迁移...

public function up()
{
  Schema::enableForeignKeyConstraints();
  Schema::create('class_tbl', function (Blueprint $table) {
    $table->integer('class_id')->unsigned()->primary();
    $table->string('course', 10);
    $table->string('section', 5);
    $table->string('school_year', 10);
    $table->integer('prof_id')->unsigned();
  });

  Schema::table('class_tbl', function($table) {
    $table->foreign('prof_id')->references('prof_id')->on('professor');
  });
}

Answer 1

嗯...一个可以为空的外键？试试这个......

Schema::create('student', function (Blueprint $table) {
        $table->integer('student_id')->unsigned()->primary();
        $table->string('student_name', 200);
        $table->string('student_email', 50);
        $table->integer('class_id')->unsigned();
        $table->foreign('class_id')->references('class_id')->on('class_tbl');
        $table->string('password', 100);
        $table->rememberToken();
        $table->timestamps();
    });

   Schema::create('class_tbl', function (Blueprint $table) {
    $table->integer('class_id')->unsigned()->primary();
    $table->string('course', 10);
    $table->string('section', 5);
    $table->string('school_year', 10);
    $table->integer('prof_id')->unsigned();
    $table->foreign('prof_id')->references('prof_id')->on('professor');
  });

在laravel中迁移我的表时出错

1 个答案: