entity framework book

If lazy loading enable = true is not set in the Entity Framework, the handler must handle the loading of the metadata, for example, using load or include, however, because the include parameter number is string, it is very difficult for a person to find the parameter easily after tablename is changed with string, so I want to introduce an extension method. // Adventureworkslt2008r2entities context = new adv

Entity Framework 6 Recipes 2nd Edition (9-5) Translation-> delete a disconnected Entity, entityrecipes 9-5. delete a disconnected entity Problem We need to delete the object retrieved from WCF. Solution Let's assume that we have the payment and Bill model of the entity as sh

Entity SQL is the SQL class language provided by the Ado.net Entity Framework to support the Entity Data Model (EDM). Entity SQL can be used for object queries and queries executed using the EntityClient provider. L Key Words Value keyword ESQL provides a SELECT value cla

Validate EntityYou can write the custom server side validation for any entity. To accomplish this, override validateentity method of DBContext as shown below.protected OverrideSystem.Data.Entity.Validation.DbEntityValidationResult validateentity (Dbentityentry entityentry, system.collections.generic.idictionaryObject,Object>items) { if(entityentry.entity isStudent) { if(entityentry.currentvalues.getvaluestring> ("Studentname") =="") {

By default, only the reference of the LINQ assembly is added to Web. config generated in MVC. If Entity Framework (EF) is used as the orm of MVC, you need to add the Assembly reference in webconfig: For example: ...... Asp.net MVC 2 cocould not load type 'System. Web. MVC. viewpage If problems such as cocould not load type 'System. Web. MVC. viewpage Code Code highlighting produced by Actipro CodeHighlight

Ado. netEntity Framework Overview The new version of ADO. NET features the New Entity Framework. It allows developers to focus on data through the Object Model (instead of the logical/Relational Data Model. The Entity Framework helps to abstract the logical data architectu

Entity Framework object Framework formation tour-several typical operations on the interface (8), entityframework In the previous article, "The Journey of Entity Framework formation -- separation and combination of data transmission model DTO and

Domain Layerentity is one of the core concepts of DDD (domain driven design). Eric Evans describes this as "a lot of objects are not defined by their attributes, but by a series of continuity events and Identity Definitions" (a reference to the domain-driven design book). Translators note that objects are not defined by their attributes, but by their linear continuity and identity. Therefore, an entity is

naming foreign key columns when creating foreign keys based on default conventions. In the programming Entity Framework Code first book, the 3 types of foreign key column names are agreed by: [Target type key name], [target type name] + [Target type Ke Y name], or [Navigation property name] + [target type key name], the corresponding Chinese translation is: [The

ways of naming foreign key columns when creating foreign keys based on default conventions. In the programming Entity Framework Code first book, the 3 types of foreign key column names are agreed by:[target type key name], [target type name] + [target TYP E Key name], or [Navigation property name] + [target type key name], the corresponding Chinese translation i

In the previous chapters, we have designed a simple domain model, and then we want to be able to implement the domain model persistence and query. In Apworks, a warehousing infrastructure for the entity Framework, NHibernate, and MongoDB is implemented. In this section, I'll show you how to use the Entity Framework-bas

Apworks Framework practice (6): using the Entity Framework-based warehouse infrastructure, apworksentity In the previous chapter, we have designed a simple domain model. Next we hope to realize the persistence and query of the domain model. Apworks provides the warehousing infrastructure for Entity

), the Fix-up will also ensure that the customer. Orders attribute contains those Orders. This is the real reason why Include ("Orders") is not used in my query. This avoids the problem and leads to a new problem: Can Customer. Orders be sorted? Unfortunately, there is no official solution. This is not a feature we want to support. We don't have to spend time-we need to test it to make sure it works in every scenario. You know that is an important QA issue. Although there are opponents, this can

? Unfortunately, there is no official solution. This is not a feature we want to support. We don't have to spend time-we need to test it to make sure it works in every scenario. You know that is an important QA issue. Although there are opponents, this can work in any way... Why? My guess is to execute sorting in the query, write an object based on datareader and finally fix-up.CodeThere are side effects. Now, theoretically you can use this feature in the project... However, note that

to create the same ing. Figure 1-6 key points in designer Modeling Of course, the key points in designer modeling are far more than those shown in Figure 1-6. This book covers all aspects of designer modeling. In some cases, beyond the capabilities of the designer, this book will show how to handle this situation by modifying the underlying. edmx file. This file contains the complete model definition, inc

Before writing the data Layer D layer when there are many SQL statements, how to omit the tedious SQL statements, Microsoft provides a good way-Entity Framework-entity framwork. An object mapping mechanism that supports. NET developers use domain-specific objects to come out of relational data, eliminating the need for most of the data access code that developers

Entity Framework object Framework formation journey -- using Fluent API configuration in Code First mode (6), -- codefluent The previous article Entity Framework formation journey-Code First Framework Design (5) introduced the exp

and logical models can be one-to-a-kind associations,but it doesn't have to be linked in a one-to-one way,this isEDMthe function,like,an entity in the conceptual model,This entity actually derives its data from multiple tables in the database.You can see for yourself.XMLfile,can read it all ..Speaking of this ,,error when importing a table without a primary key in the