laravel - @Laravel 迁移：无法在 laravel 中添加外键约束

问题描述

我正在尝试在 Laravel 中创建外键，但是当我使用 artisan 迁移我的表时，我抛出了以下错误：

λ php artisan migrate
Migration table created successfully.


[Illuminate\Database\QueryException]
  SQLSTATE[HY000]: General error: 1215 Cannot add foreign key constraint (SQL: alter table `fees` add constraint `fee
  s_fee_type_id_foreign` foreign key (`fee_type_id`) references `feetypes` (`fee_type_id`))


  [PDOException]
  SQLSTATE[HY000]: General error: 1215 Cannot add foreign key constraint

我的迁移代码是这样的：

费用

<?php

use Illuminate\Support\Facades\Schema;
use Illuminate\Database\Schema\Blueprint;
use Illuminate\Database\Migrations\Migration;

class CreateFeesTable extends Migration
{
    /**
     * Run the migrations.
     *
     * @return void
     */
    public function up()
    {
        Schema::create('fees', function (Blueprint $table) {
            $table->increments('fee_id');
            $table->integer('academic_id')->unsigned();
            $table->integer('level_id')->unsigned();
            $table->integer('fee_type_id');
            $table->string('fee_heading', 100)->nullable();
            $table->float('amount', 8, 2);
            $table->foreign('academic_id')->references('academic_id')->on('academics');
            $table->foreign('level_id')->references('level_id')->on('levels');
            $table->foreign('fee_type_id')->references('fee_type_id')->on('feetypes');
        });
    }

    /**
     * Reverse the migrations.
     *
     * @return void
     */
    public function down()
    {
        Schema::dropIfExists('fees');
    }
}

类型

<?php

use Illuminate\Support\Facades\Schema;
use Illuminate\Database\Schema\Blueprint;
use Illuminate\Database\Migrations\Migration;

class CreateFeetypesTable extends Migration
{
    /**
     * Run the migrations.
     *
     * @return void
     */
    public function up()
    {
        Schema::create('feetypes', function (Blueprint $table) {
            $table->unsignedinteger('fee_type_id');
            $table->string('fee_type', 100);
        });
    }

    /**
     * Reverse the migrations.
     *
     * @return void
     */
    public function down()
    {
        Schema::dropIfExists('feetypes');
    }    
}

关于我做错了什么的任何想法，我现在想得到这个，因为我需要创建很多表，例如用户、学生、Leves 等。理想情况下，我想创建包含这个的表带有外键的数据，即费用和费用类型。

希望有人可以帮助我开始。

标签： laravellaravel-migrations

检查所有数据类型是否与引用的数据类型匹配。

public function up()
{
    Schema::create('fees', function (Blueprint $table) {
        $table->increments('fee_id');
        $table->unsignedInteger('academic_id');
        $table->unsignedInteger('level_id');
        $table->unsignedInteger('fee_type_id');
        $table->string('fee_heading', 100)->nullable();
        $table->float('amount', 8, 2);
        $table->foreign('academic_id')->references('academic_id')->on('academics');
        $table->foreign('level_id')->references('level_id')->on('levels');
        $table->foreign('fee_type_id')->references('fee_type_id')->on('feetypes');
    });
}

检查levels 中的level_id、academics 中的academic_id、feetypes 中的fee_type_id 也是unsignedInteger或autoincrement并将您的表格创建脚本更改为以上一个。

laravel - @Laravel 迁移：无法在 laravel 中添加外键约束

问题描述

解决方案

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