5、Entity Framework Core 开发指南:实体类、上下文类与数据库架构生成

Entity Framework Core 开发指南:实体类、上下文类与数据库架构生成

在开发过程中,Entity Framework Core 是一个强大的工具,它能帮助我们高效地处理数据库操作。下面将详细介绍 Entity Framework Core 中实体类、上下文类的规则以及数据库架构生成的相关内容。

自创建实体类规则

实体类是 POCO(Plain Old CLR Object)对象,不需要继承基类或实现接口,但必须有一个无参数构造函数,以便 Entity Framework Core 在将数据库表行实例化时使用。

NuGet 包

实现实体类时,不需要引用任何 Entity Framework Core 的 NuGet 包。但如果使用如 [Key] 和 [StringLength] 这样的数据注解,则需要引用 System.ComponentModel.Annotations.dll (在经典 .NET Framework 中),或者在 .NET Core 和 .NET Standard 中引用 NuGet 包 System.ComponentModel.Annotations (https://www.nuget.org/packages/System.ComponentModel.Annotations)。

数据注解属性

数据库表中要创建的每个列都必须由一个属性表示。属性可以是带有 {get; set;} 的自动属性,也可以是带有 getter 和

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深度学习工具包Deprecation notice.-----This toolbox is outdated and no longer maintained.There are much better tools available for deep learning than this toolbox, e.g. [Theano](http://deeplearning.net/software/theano/), [torch](http://torch.ch/) or [tensorflow](http://www.tensorflow.org/)I would suggest you use one of the tools mentioned above rather than use this toolbox.Best, Rasmus.DeepLearnToolbox================A Matlab toolbox for Deep Learning.Deep Learning is a new subfield of machine learning that focuses on learning deep hierarchical models of data.It is inspired by the human brain's apparent deep (layered, hierarchical) architecture.A good overview of the theory of Deep Learning theory is[Learning Deep Architectures for AI](http://www.iro.umontreal.ca/~bengioy/papers/ftml_book.pdf)For a more informal introduction, see the following videos by Geoffrey Hinton and Andrew Ng.* [The Next Generation of Neural Networks](http://www.youtube.com/watch?v=AyzOUbkUf3M) (Hinton, 2007)* [Recent Developments in Deep Learning](http://www.youtube.com/watch?v=VdIURAu1-aU) (Hinton, 2010)* [Unsupervised Feature Learning and Deep Learning](http://www.youtube.com/watch?v=ZmNOAtZIgIk) (Ng, 2011)If you use this toolbox in your research please cite [Prediction as a candidate for learning deep hierarchical models of data](http://www2.imm.dtu.dk/pubdb/views/publication_details.php?id=6284)```@MASTERSTHESIS\{IMM2012-06284, author = "R. B. Palm", title = "Prediction as a candidate for learning deep hierarchical models of data", year = "2012",}```Contact: rasmusbergpalm at gmail dot comDirectories included in the toolbox-----------------------------------`NN/` - A library for Feedforward Backpropagation Neural Networks`CNN/` - A library for Convolutional Neural Networks`DBN/` - A library for Deep Belief Networks`SAE/` - A library for Stacked Auto-Encoders`CAE/` - A library for Convolutional Auto-Encoders`util/` - Utility functions used by the libraries`data/` - Data used by the examples`tests/` - unit tests to verify toolbox is workingFor references on each library check REFS.mdSetup-----1. 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