orm

Laravel4 Model primary key value is lost after insert

由 ぐ巨炮叔叔 提交于 2020-01-14 22:32:13
问题 <?php // Model class ProfileDelivery extends \Eloquent { protected $table = 'profile_delivery'; protected $guarded = array(); public $timestamps = FALSE; } // Somewhere $deliveryGuy->id = 1; print $deliveryGuy->id; // Prints 1 if (!$deliveryGuy->save()) { throw new \Exception('Cant save .'); } print $deliveryGuy->id; // Prints 0 Can anyone explain me why the ID value is lost? 回答1: Not sure if you solved this for your situation but in Laravel 5.1 this just happened to me - the primary key of

Laravel4 Model primary key value is lost after insert

由 有些话、适合烂在心里 提交于 2020-01-14 22:31:57
问题 <?php // Model class ProfileDelivery extends \Eloquent { protected $table = 'profile_delivery'; protected $guarded = array(); public $timestamps = FALSE; } // Somewhere $deliveryGuy->id = 1; print $deliveryGuy->id; // Prints 1 if (!$deliveryGuy->save()) { throw new \Exception('Cant save .'); } print $deliveryGuy->id; // Prints 0 Can anyone explain me why the ID value is lost? 回答1: Not sure if you solved this for your situation but in Laravel 5.1 this just happened to me - the primary key of

Laravel4 Model primary key value is lost after insert

由 ╄→尐↘猪︶ㄣ 提交于 2020-01-14 22:31:18
问题 <?php // Model class ProfileDelivery extends \Eloquent { protected $table = 'profile_delivery'; protected $guarded = array(); public $timestamps = FALSE; } // Somewhere $deliveryGuy->id = 1; print $deliveryGuy->id; // Prints 1 if (!$deliveryGuy->save()) { throw new \Exception('Cant save .'); } print $deliveryGuy->id; // Prints 0 Can anyone explain me why the ID value is lost? 回答1: Not sure if you solved this for your situation but in Laravel 5.1 this just happened to me - the primary key of

MyBatis与Hibernate有什么异同？

由 社会主义新天地 提交于 2020-01-14 20:30:39
相同点 ：都屏蔽了JDBC API的底层访问细节，使用我们不用与JDBC API打交道，就可以访问数据库。 不同点 ： 1.Hibernate是一个全自动的ORM映射框架，它可以自动生成并执行SQL语句，将得到结果集中的字段自动映射到指定的实体类的属性上面。 而MyBatis需要我们在SQL映射文件中编写SQL语句，然后再通过这个SQL映射文件，将SQL所需要的参数，以及返回的结果 字段 映射到指定实体类中的 属性 上面。 2.对于一些不太复杂的SQL查询，Hibernate可以很好帮我们完成，但是对于特别复杂SQL的查询，我们就使用MyBatis。 来源： CSDN 作者： 冷风的代码 链接： https://blog.csdn.net/weixin_43891448/article/details/103977915

How to map query for iBATIS with parameterized column in select clause?

由 房东的猫 提交于 2020-01-14 18:58:19
问题 I want to have a method that finds a certain value from a column of a particular table in the database, where the name of the column is passed in as a parameter. So the Java method would have the following signature: public Integer getFoo(String column) throws DataAccessException; My attempted mapping for this query is the following: <select id="getFoo" parameterClass="java.lang.String" resultClass="java.lang.Integer"> select min($column$) from daily_statistics where $column$ > 0 </select>

Polymorphic cross-associations on Entity Framework

由 半腔热情 提交于 2020-01-14 11:12:58
问题 OK, this is an interesting and most importably real urgent problem for me to solve... In order for others to neatly comprehend it, I've stretched myself to make a well illustrated post. The Object Model So I have this simple, easy and "beautiful" model in mind. See the first picture. (You can ignore PathEntry , it's not relevant in my situation.) The idea is that a MediaFeedItem owns: a collection of ThumbnailFileEntries (accesible through the ThumbnailFiles property) at most 1 raw FileEntry

Polymorphic cross-associations on Entity Framework

由 依然范特西╮ 提交于 2020-01-14 11:07:38
问题 OK, this is an interesting and most importably real urgent problem for me to solve... In order for others to neatly comprehend it, I've stretched myself to make a well illustrated post. The Object Model So I have this simple, easy and "beautiful" model in mind. See the first picture. (You can ignore PathEntry , it's not relevant in my situation.) The idea is that a MediaFeedItem owns: a collection of ThumbnailFileEntries (accesible through the ThumbnailFiles property) at most 1 raw FileEntry

Polymorphic cross-associations on Entity Framework

由 喜夏-厌秋 提交于 2020-01-14 11:07:28
问题 OK, this is an interesting and most importably real urgent problem for me to solve... In order for others to neatly comprehend it, I've stretched myself to make a well illustrated post. The Object Model So I have this simple, easy and "beautiful" model in mind. See the first picture. (You can ignore PathEntry , it's not relevant in my situation.) The idea is that a MediaFeedItem owns: a collection of ThumbnailFileEntries (accesible through the ThumbnailFiles property) at most 1 raw FileEntry

所谓的持久层框架？ORM框架？以及Hibernate和Mybatis区别？

由 久未见 提交于 2020-01-14 08:47:22
ORM框架？ Object Relational Mapping，对象-关系映射。 项目中的业务实体有两种表现形式：对象和关系数据，即在内存中表现为对象，在数据库中表现为关系数据。 为什么需要ORM框架？ ORM框架是对象关系映射，那为什么要映射mapping？ 因为对象之间可以存在关联和继承关系，但是在数据库中，关系数据无法表达多对多关联和继承关系。（ps：在数据库原理中，会把逻辑上的多对多转换为多个一对关系才能实现）因此，对象和关系（业务实体的两种表现形式）想要映射正确，项目系统一般以中间件的形式，即持久层框架。 Hibernate？ Hibernate是一个开源的对象关系映射框架。 它对jdbc进行了非常轻量级的对象封装，将pojo（普通的Java对象）与数据库表建立映射关系，是一个全自动的ORM框架，甚至自动生成SQL语句，自动执行。 因此，程序员可以随心所有地使用对象编程思维来操纵数据库。 Hibernate特点： Hibernate通过修改一个“持久化”对象的属性，从而修改数据库表中对应的记录数据 提供线程和进程两个级别的缓存提升应用程序性能 有丰富的映射方式将 Java对象之间的关系（POJO） 转换为 数据库表之间的关系 屏蔽不同数据库实现之间的差异。在Hibernate中只需通过“方言”的形式指定当前使用的数据库，就可以根据底层数据库的实际情况生成适合的SQL语句

Translating query with JOIN expressions and a generic relation to Django ORM

由 无人久伴 提交于 2020-01-14 04:32:06
问题 class Business(models.Model): manager = models.ForeignKey(User, on_delete=models.CASCADE) #... class Event(models.Model): business = models.ForeignKey(Business, on_delete=models.CASCADE) text = models.TextField() when = models.DateTimeField() likes = GenericRelation('Like') class Like(models.Model): person = models.ForeignKey(User, on_delete=models.CASCADE) content_type = models.ForeignKey(ContentType) object_id = models.PositiveIntegerField() content_object = GenericForeignKey('content_type'
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