Laravel 5外键迁移错误

Question

我在尝试重置迁移时遇到问题。我正在使用 oracle sql，所以当问题出现时，我首先想到我已经完成了，我现在在我的 sql 开发人员中清空了数据库，我没有看到 table，但是如果我运行修补程序每 table 被创建一次。当我尝试回滚我的迁移时，我收到一个错误，指出我在某些 table 中有外键：table 中的 unique/primary 键被外键引用，但是当我尝试删除约束 artisan 说 table 没有这个约束。

这是我的迁移文件：类别 table:

public function up()
{
    Schema::create('categories', function(Blueprint $table)
    {
        $table->increments('id');
        $table->string('name');
        $table->integer('parent');
    });
    Schema::create('article_category', function(Blueprint $table){
        $table->integer('article_id')->unsigned()->index();
        $table->foreign('article_id')->references('id')->on('articles')->onDelete('cascade');
        $table->integer('category_id')->unsigned()->index();
        $table->foreign('category_id')->references('id')->on('categories')->onDelete('cascade');
        $table->timestamps();
    });
}

/**
 * Reverse the migrations.
 *
 * @return void
 */
public function down()
{
    Schema::drop('article_category');
    Schema::drop('categories');

}

文章table:

public function up()
{
    Schema::create('articles', function(Blueprint $table){

        $table->increments('id');
        $table->longText('title');
        $table->integer('user_id')->unsigned();
        $table->string('excerpt',255);
        $table->longText('body');
        $table->integer('likes')->default(0);
        $table->longText('sourceName');
        $table->longText('linkURL');
        $table->integer('views')->default(0);
        $table->timestamp('published_at');
        $table->timestamps();

        $table->foreign('user_id')->references('id')->on('users')->onDelete('cascade');

    });


}



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

我的角色table:

public function up()
{
    Schema::create('roles', function(Blueprint $table)
    {
        $table->increments('id');
        $table->string('name');
        $table->timestamps();
    });
    Schema::create('role_user', function(Blueprint $table){
        $table->integer('role_id')->unsigned()->index();
        $table->foreign('role_id')->references('id')->on('roles')->onDelete('cascade');
        $table->integer('user_id')->unsigned()->index();
        $table->foreign('user_id')->references('id')->on('users')->onDelete('cascade');
        $table->timestamps();
    });
}

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

我的标签 table:

public function up()
{
    Schema::create('tags', function(Blueprint $table)
    {
        $table->increments('id');
        $table->string('name');
        $table->timestamps();
    });
    Schema::create('article_tag', function(Blueprint $table){
        $table->integer('article_id')->unsigned()->index();
        $table->foreign('article_id')->references('id')->on('articles')->onDelete('cascade');
        $table->integer('tag_id')->unsigned()->index();
        $table->foreign('tag_id')->references('id')->on('tags')->onDelete('cascade');
        $table->timestamps();
    });
}

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

所以，基本上我的数据库是空的，但我不能运行任何东西。如果我运行 php artisan migrate 没有创建 table，但是如果我运行 php artisan migrate:refresh/rollback/reset unique/primary table 中的键在删除 table 文章时被外键引用。我已经对此进行了搜索，但没有找到适合我的问题的任何内容希望我能在这里找到解决方案

Answer 1

你应该 dropForeign 在你放下 table 之前。

示例：

public function up()
{
    Schema::create('tags', function(Blueprint $table)
    {
        $table->increments('id');
        $table->string('name');
        $table->timestamps();
    });
    Schema::create('article_tag', function(Blueprint $table){
        $table->integer('article_id')->unsigned()->index();
        $table->foreign('article_id')->references('id')->on('articles')->onDelete('cascade');
        $table->integer('tag_id')->unsigned()->index();
        $table->foreign('tag_id')->references('id')->on('tags')->onDelete('cascade');
        $table->timestamps();
    });
}

/**
 * Reverse the migrations.
 *
 * @return void
 */
public function down()
{
    Schema::table('article_tag', function (Blueprint $table) {
        $table->dropForeign('article_tag_article_id_foreign');
        $table->dropForeign('article_tag_tag_id_foreign');
    });
    Schema::drop('article_tag');
    Schema::drop('tags');
}

Laravel 5外键迁移错误

Laravel 5 foreign key migration error

php

migration

oracle

laravel

laravel-5