1. 06 | Integrating extra features and looking forward
Christopher Harrison | Content Developer, Microsoft
Adam Tuliper | Technical Evangelist, Microsoft

2. Module Overview Stored procedures
Increasing user experience with concurrency detection
A few best practices
Looking forward with Entity Framework 7

3. Stored procedures

4. Store procedures Why use stored procedures? Limits dynamic sql
Single point to secure – easier permissions
Know exactly how DB is being queries
Limits dynamic sql
Still possible with sprocs, just more manual effort
In general performance is _not_ a reason
Virtually the same as sql query (pendulum swings both ways)

5. Stored procedures Support came as XX
In the past could simply Database.SqlQuery
Could map in the designer (which is going away)
Code first will generate procedures
context.Database.SqlQuery<myEntityType>(
new SqlParameter("param1", param1),
new SqlParameter("param2", param2),
new SqlParameter("param3", param3) );

6. Integrating stored procedures

7. Increasing user experience with concurrency detection

8. Concurrency As Chris showed, easy to implement via concurrency token
[TimeStamp]
modelBuilder.Entity<YourEntity>()
.Property(e => e.Timestamp)
.IsRowVersion();
Change detection can be enhanced via MVC Action Filters
Let’s give the user the choice on how to proceed

9. Concurrency detection and user choice

10. A few best practices

11. Helpful hints in a web world
Since the web layers (controller to view) are disconnected
Always convert results to IEnumerable via .ToList()
Ex. context.Albums.Where(o=>o.Title.Contains(search).ToList()
Disable lazy loading in web environments
context.Configuration.LazyLoadingEnabled = false;
Use .Include to load related entities
DbContext is not thread safe. Do not cache it!
Always dispose DbContext when done

12. Context lifetime When context is gone, connection is gone
Can’t (and shouldn’t) use connection from MVC view
Get data, send to view
Always execute result set when needed before exiting using()
using (var context = new MusicContext()) {
var albums = context.Albums
.Where(o=>o.Title.Contains(search))
.ToList());
return View(albums); }

13. Watch out for… If you have two+ context classes
One from selecting auth during app creation (Identity)
One for your other entities
Migrations should specify separate folders
Enable-Migrations –MigrationsDirectory IdentityMigrations
Enable-Migrations –MigrationsDirectory MusicStoreMigrations
For complex joins, keep an eye on queries
Doing lots of inserts? AutoDetectChangesEnabled = false;

14. Async when appropriate
EF supports async queries
Async allows current thread to be used elsewhere
Useful in case of network, db delays (long operations)
Although not all the time, caution of overloading db
public async Task<ActionResult> Create(…) {
if (ModelState.IsValid)
db.Albums.Add(album);
await db.SaveChangesAsync();
return RedirectToAction("Index"); }
return View(album);

15. Consider Connection resiliency
This is a connection retry policy
Works great with async
Four modes
DefaultExecutionStrategy
DefaultSqlExecutionStrategy
DbExecutionStrategy
SqlAzureExecutionStrategy
throws RetryLimitExceededException

16. Connection Resiliency & Async

17. Looking forward with Entity Framework 7

18. Notable new features Designer has been removed
Code first only
Rewritten from ground up with performance in mind
New platforms
New data stores
In memory database
Update-Database now split
Apply-Migration
Script-Migration

19. EF 7 Quick Tour

20. Resources Additional patterns Reducing Code First Database Chatter
ef-5-using-mvc-4/implementing-the-repository-and-unit-of-work- patterns-in-an-asp-net-mvc-application
Reducing Code First Database Chatter
EF7 Project home