When configuring a relationship with the fluent API, you start with the EntityTypeConfiguration instance and then use the HasRequired, HasOptional, or HasMany method to specify the type of relationship this entity participates in. The HasRequired and HasOptional methods take a lambda expression that ...
Entity Framework 6 (EF6) is a tried and tested object-relational mapper (O/RM) for .NET with many years of feature development and stabilization.As an O/RM, EF6 reduces the impedance mismatch between the relational and object-oriented worlds, enabling developers to write applications that ...
either depend on EF6's underlying Entity Data Model (EDM) and/or are complex features with relatively low return on investment. We always welcome feedback, but while EF Core enables many things not possible in EF6, it is conversely not feasible for EF Core to support all the features of...
The ModificationFunctionMapping element can also map the insert and delete functions for many-to-many associations in the conceptual model to stored procedures in the underlying database. Stored procedures to which modification functions are mapped must be declared in the storage model. For more ...
一对一关系 (One-to-One)简介一对一关系表示两个实体之间存在一对一的关联,例如,一个人有一个护照。...问题2:主键选择不当避免策略:考虑使用共享主键或外键作为主键策略,确保关系的唯一性。...(Many-to-Many)简介多对多关系表示两个实体集合可以相互关联,比如学生和课程的关系。...,正确理解和应用一对一、...
配置多对多关系:在EF6中,可以使用Fluent API来配置多对多关系。可以在DbContext的OnModelCreating方法中使用HasMany和WithMany方法来配置多对多关系,并指定桥表的名称和外键。 进行查询操作:在进行多对多查询时,可以使用LINQ查询语句来获取满足条件的数据。可以通过导航属性来访问相关的实体类,并进行筛选、排序等操作。
Entity Framework 6 (EF6) is a tried and tested object-relational mapper for .NET with many years of feature development and stabilization. It eliminates the need for most of the data-access code that developers usually need to write.
and many other nice-to-have bits. Code generation is completely customizable via T4 templates. The tool installs templates that target both EF6 and EFCore, and generate both a code-first DbContext class and POCO entity classes. The EF6 template's DbContext code is written to allow consumpti...
然后,我们使用Fluent API来定义了实体类之间的映射关系。具体来说,我们使用HasMany方法定义了Customer和Order之间的一对多关系,使用WithRequired方法定义了Order必须有一个Customer,使用HasForeignKey方法定义了Order的外键为CustomerId,使用WillCascadeOnDelete方法定义了删除Customer时级联删除所有相关的Order。
returning either a reference object (if the multiplicity is either one or zero-or-one) or a collection (if the multiplicity is many). You may also choose to have one-way navigation, in which case you define the navigation property on only one of the types that participates in the relation...