php – Laravel 4.2多对多关系,使用其他东西然后默认ID
发布时间:2020-12-14 19:39:23 所属栏目:大数据 来源:网络整理
导读:我有两个模型,他们都没有使用表中的ID,但字段internal_id.所以我定制了我的枢轴架构,但我一直坚持连接它们.我得到错误: General error: 1215 Cannot add foreign key constraint (SQL: alter table `SEOshop_category_product` add constraint SEOshop_cate
我有两个模型,他们都没有使用表中的ID,但字段internal_id.所以我定制了我的枢轴架构,但我一直坚持连接它们.我得到错误:
General error: 1215 Cannot add foreign key constraint (SQL: alter table `SEOshop_category_product` add constraint SEOshop_category_product_category_id_foreign foreign key (`category_id`) references `SEOshop_categories` (`internal_id`) on delete cascade) 迁移的代码是: Schema::create('SEOshop_category_product',function(Blueprint $table) { $table->increments('id'); $table->integer('category_id')->unsigned()->index(); $table->foreign('category_id')->references('internal_id')->on('SEOshop_categories')->onDelete('cascade'); $table->integer('product_id')->unsigned()->index(); $table->foreign('product_id')->references('internal_id')->on('SEOshop_products')->onDelete('cascade'); $table->timestamps(); }); 作为SEOshop_categories.internal_id的SEOshop_products.internal_id这两个字段都是现有的,列类型都是int(11). 谁能告诉我出了什么问题? 表SEOshop_categories和SEOshop_products的迁移 //SEOshop_products public function up() { Schema::create('SEOshop_products',function(Blueprint $table) { $table->increments('id'); $table->integer('shop_id'); $table->integer('internal_id')->signed()->index(); $table->integer('internal_variant_id'); $table->string('visible'); $table->string('tags'); $table->timestamps(); }); } //Table SEOshop_categories public function up() { Schema::create('SEOshop_categories',function(Blueprint $table) { $table->increments('id'); $table->integer('internal_id')->signed()->index(); $table->datetime('SEOshop_created_at'); $table->datetime('SEOshop_updated_at'); $table->text('full_description'); $table->timestamps(); }); } 好的,所以现在我已经创建了我的表,它的工作原理应该如何.我需要让我的产品有类别(多2个).所以我用 SEOshopProduct::find(1)->with('categories')->get(); 在dd()之后,类别为空,我查看了我的查询如何调用它: [8] array(3) { ["query"] "select `SEOshop_categories`.*,`SEOshop_category_product`.`product_id` as `pivot_product_id`,`SEOshop_category_product`.`category_id` as `pivot_category_id` from `SEOshop_categories` inner join `SEOshop_category_product` on `SEOshop_categories`.`id` = `SEOshop_category_product`.`category_id` where `SEOshop_category_product`.`product_id` in (?)" ["bindings"] array(1) { [0] 8 } ["time"] 0.37 } 产品和类别的internal_id大于10.000,我在查询中看不到它. 我的模特: 产品: public function categories(){ return $this->belongsToMany('SEOshopCategory','SEOshop_category_product','product_id','category_id'); } 分类: public function products(){ return $this->belongsToMany('SEOshopCategory','category_id','product_id'); } 解决方法
要设置外键约束,字段定义需要完全匹配.但是,在这种情况下,SEOshop_category_product.category_id字段被定义为UNSIGNED INT,但引用的SEOshop_categories.internal_id字段被定义为SIGNED INT.对于您的产品的外键也是如此.
因此,您可以将类别和产品表上的internal_id字段更新为未签名,也可以更新数据透视表上的外键字段以进行签名. (编辑:李大同) 【声明】本站内容均来自网络,其相关言论仅代表作者个人观点,不代表本站立场。若无意侵犯到您的权利,请及时与联系站长删除相关内容! |