Home » Microsoft » 70-518 » Which 2 actions should you perform?
You are developing a Windows Application.
New features that require changes to be made to the database schema are added to the application every week.
You need to ensure that the changes made to the database schema do not require the application to be recompiled.
Which 2 actions should you perform?
A. Modify the XML mapping file when the schema changes occur
B. Modify the conceptual schema XML file when the schema changes occur
C. Build a storage model and use it to access data from the business entities
D. Build a conceptual model and use it to access data from the business entities
Correct Answer: AD
Explanation/Reference:
References:
If you use the Entity Framework and might need to update the database structure without recompiling your application, choose to copy the model and mapping schemas to the build output directory rather than embedding them in the output assembly by selecting your model and setting Metadata Artifact Process to Copy To Output Directory.
These three schemas work together to map a relational database to .NET classes. Within your project, they are defined within the .edmx file. When you build your project with Copy To Output Directory selected, the schemas will be created as three separate XML files as follows:
¦¦ Store Schema Definition Language (SSDL) Describes the tables and fields in a database
¦¦ Conceptual Schema Definition Language (CSDL) Describes your .NET Framework classes
¦¦ Mapping Schema Language (MSL) Describes how the Common Language Runtime (CLR) will convert between the database described in the SSDL file and the classes described in the CSDL file.
By not compiling them into the assembly, you can update these files later and restart the application to adapt to changes in the underlying database. While you could update the files manually, it is easier to use the Visual Studio wizards to update the model, build the project, and use the updates files generated by Visual Studio.
