relationship

I have a problem with replicating one of my models with all the relationships. The database structure is as follows: Table1: products id name Table2: product_options id product_id option Table3: categories id name Pivot table: product_categories product_id category_id Relationships are: product hasMany product_options product belongsToMany category (trough product_categories) I would like to clone a product with all the relationships. Currently here is my code: $product = Product::with('options')->find($id); $new_product = $product->replicate(); $new_product->push(); foreach($product->options

I am working on an application that will be used as an extensible framework for other applications. One of the fundamental classes is called Node, and Nodes have Content. The SQL tables look like this: TABLE Node ( NodeId int, .... etc ) TABLE NodeContentRelationship ( NodeId int, ContentType string, ContentId int) It will be up to the developers extending the application to create their own content types. Clearly this is bad from a relationship-database point of view as it is not possible to add a foreign key relationship to NodeContentRelationship.ContentId, even though it is a foreign key

I am trying to build a CoreData model similar to Twitter user when User can have many other users who follows him and many other users followed by him. I attached the model that I have tried to use but seems it is getting to complicating to retrieve followers. What is the best way to deal with this situation? I think you need to create a second relationship ( followedBy ) and make that the inverse. 来源： https://stackoverflow.com/questions/12709842/ios-coredata-inverse-relationships-to-itself

之前使用freemarker导出word，可以在PC上打开。但是它不能在手机上打开，因为它是xml格式的。所以后来又修改了导出方式，导出标准格式的word. （具体步骤和引用文件不再赘述，可先参考之前文章） 之前的导出方式： 请戳====>java使用freemarker导出word 一、文件结构 首先我们来看一下标准格式的word有哪些东西组成。 和上文一样，创建一个word文档trip.docx。 把后缀名docx改为zip 3. 解压后，查看文件夹内容结构如下： 查看各个文档后我们会发现 根目录下的**[Content_Types].xml 中指定文件的配置，比如图片格式，主题文件，样式文件等等； word文件夹下的 media 文件夹存放文档中的图片; word文件夹下的_rels文件夹下的 document.xml.rels 中则指定了文档中用的图片id和图片名称； word文件夹下的 document.xml 则是文档内容，也是我们要写入的文档模板。 word文件夹下的 header1.xml 则是指定页眉 这里没有写页脚，如果有页脚，会有 footer.xml**的文件生成。 想用和需要修改的就是上面几个文件了。 二、思路分析 使用 document.xml 修改成需要的word模板 修改 header1.xml 中的页眉 在**[Content_Types].xml

I'm following the Flask-SQLAlchemy tutorial. I have Flask 0.9, sqlalchemy 0.7.8 and flask-sqlalchemy 0.16 on python 2.6. I'm trying to create a "one to many" relationship, like in their tutorial. class Person(db.Model): id = db.Column(db.Integer, primary_key=True) name = db.Column(db.String(50)) addresses = db.relationship('Address', backref='person', lazy='dynamic') class Address(db.Model): id = db.Column(db.Integer, primary_key=True) email = db.Column(db.String(50)) person_id = db.Column(db.Integer, db.ForeignKey('person.id')) After that, I can create the database : from DataBase.Tables

I'm trying to add a relation to a factory model to do some database seeding as follows - note I'm trying to add 2 posts to each user public function run() { factory(App\User::class, 50)->create()->each(function($u) { $u->posts()->save(factory(App\Post::class, 2)->make()); }); } But its throwing the following error Argument 1 passed to Illuminate\Database\Eloquent\Relations\HasOneOrMany::s ave() must be an instance of Illuminate\Database\Eloquent\Model, instance of Illuminate\Database\Eloquent\Collection given I think its something to do with saving a collection. If re-write the code by calling

Is it possible to have an association between two domain classes (i.e. belongsTo ) if the other domain class uses a different datasource? The two datasources are different database drivers too. I suspect this may not be possible, but I wanted to reach out to the community here to see if it was possible. Right now I'm trying to do it and I am getting the usual suspected Hibernate error: Invocation of init method failed; nested exception is org.hibernate.MappingException: An association from the table domain_class_A refers to an unmapped class: DomainClassB Sample: class DomainClassA { static