php - 从营销事件表中，我想删除营销事件，但无法删除..发生以下错误

Question

SQLSTATE[23000]: Integrity constraint violation: 1451 Cannot delete or update a parent row: a foreign key constraint fails (demopurpose_fundraising.campaign_product, CONSTRAINT campaign_product_campaign_id_foreign FOREIGN KEY (campaign_id) REFERENCES campaign (id)) (SQL: delete from campaign where id = 60)

事件表架构:

Schema::create('campaign', function (Blueprint $table) {
            $table->engine='InnoDB';
            $table->increments('id');
            $table->integer('users_id')->unsigned();
            $table->foreign('users_id')->references('id')->on('users')->onDelete('cascade')->onUpdate('cascade');
            $table->string('campaign_name');
            $table->float('campaign_goal',8,2);
            $table->string('discription',400);
            $table->string('image');
            $table->string('category');
            $table->date('start_date');
            $table->date('end_date');
            $table->float('total_fund',8,2);
});

campaign_product 表架构:

Schema::create('campaign_product', function (Blueprint $table) {
            $table->engine='InnoDB';

            $table->increments('id');
            $table->integer('campaign_id')->unsigned();
            $table->foreign('campaign_id')->references('id')->on('campaign')->onDelete('cascade')->onUpdate('cascade');

            $table->integer('product_id')->unsigned();
            $table->foreign('product_id')->references('id')->on('product')->onDelete('cascade')->onUpdate('cascade');
        });

campaign_id是campaign_product删除中的外键..

我想删除广告系列..
如何删除营销事件产品然后营销事件？

Answer 1

除非您从 campaign_product 表中删除这些 campaign_id，否则您无法删除它。在删除广告系列之前，请先从 campaign_product 表中分离产品。示例:

$campaign = Campaign::query()->findOrFail($id); //find campaign
$campaign->products()->detach($campaign->product); //detach products from `campaign_products` table
$campaign->delete(); //delete the campaign

了解有关分离多对多关系记录的更多信息:https://laravel.com/docs/5.6/eloquent-relationships#updating-many-to-many-relationships