Set this property to log the SQL generated by the System.Data.Entity.DbContext to the given delegate. For example, to log to the console, set this property to System.Console.Write(System.String). 使用方法: 1)在自定义上下文中获得执行的SQL相关信息,即在自定上下文的构造函数中使用Database.Log ...
Entity relationships define the ways that entity records can be associated with records of other entities or the same entity. Creating new entity relationships creates new table relationships in the database. Use entity relationships to define specific associations that are frequently use...
2. In the Server Explorer window, if you already have a HR schema connection, expand it to connect to the database. As an example, the screen shot below identifies the HR schema as HR.ORCL. Enter HR for the User name and a password and click OK. Skip to Step 6....
PropertyValue Description Unique identifier of the associated data map. DisplayName Data Map ID IsValidForForm True IsValidForRead True LogicalName importmapid RequiredLevel ApplicationRequired Type Lookup Targets importmapIntroducedVersion展開資料表 PropertyValue Description Version in which the component ...
Database Name Connection String Name No Parameter If you do not specify the parameter in the base constructor of the context class then it creates a database in your local SQLEXPRESS server with a name that matches your {Namespace}.{Context class name}. For example, EF will create a data...
For example, you might have an entity in a conceptual model that actually derives its data from multiple tables in a database. The conceptual model and the logical model can associate entities one-to-one. However, the power of the EDM is that it does not have to link them one-to-one....
instead of operating on database objects, it operates on the entities defined in the entity model and on the objects materialized through Object Services. You can use Object Services to interact with the EDM, either by using Entity SQL or by using LINQ to Entities. Object Services allows you...
As the next figure shows, you are then presented with a tree structure of the database. From here you can select the object you would like to include in your model. If you also created Views and Stored Routines, these items will be displayed along with any tables. In this example...
Indatabases, an entity is a single person, place, or thing about which data can be stored. Entity data can be stored in a single row or involve a large data structure in arelational database. Indata modeling(the first step in the creation of a database), an entity is some unit of ...
In this strategy, which corresponds to InheritanceType.TABLE_PER_CLASS, each concrete class is mapped to a separate table in the database. All fields or properties in the class, including inherited fields or properties, are mapped to columns in the class's table in the database. This strategy...