1. Removing the SELECT * Chris Woodruff Quicken Loans

2. Platform Strategist
Technology
/chris.woodruff
@cwoodruff

4. friends

5. teamwork

6. partnerships

7. trust but verify

9. Developers use data in many ways…

10. web

11. mobile
web

12. api
mobile
web

13. api
mobile
web
data science

14. home

15. work
home

16. car
work
home

17. car
work
home
traveling

20. let’s look at LINQ private static void Main(string[] args) {
var context = new SchoolContext();
var studentsWithSameName = context.Students
.Where(s => s.FirstName == GetName())
.ToList(); }
public static string GetName()
return “Chris";

21. SQL let’s look at LINQ exec sp_executesql N'SELECT [s].[StudentId],
[s].[DoB], [s].[FirstName], [s].[GradeId],
[s].[LastName], [s].[MiddleName]
FROM [Students] AS [s]
WHERE [s].[FirstName] = nvarchar(4000)’,
@__GetName_0=N’Chris’ Go
SQL

22. include example var context = new SchoolContext();
var studentWithGrade = context.Students.Where(s => s.FirstName == "Bill")
.Include(s => s.Grade)
.Include(s => s.StudentCourses)
.FirstOrDefault();
SELECT TOP(1) [s].[StudentId], [s].[DoB], [s].[FirstName], [s].[GradeId],[s].[LastName], [s].[MiddleName], [s.Grade].[GradeId], [s.Grade].[GradeName], [s.Grade].[Section]
FROM [Students] AS [s]
LEFT JOIN [Grades] AS [s.Grade] ON [s].[GradeId] = [s.Grade].[GradeId]
WHERE [s].[FirstName] = N’Bill’

23. multiple queries to DB var context = new SchoolContext();
var studentWithGrade = context.Students.Where(s => s.FirstName == "Bill")
.Include(s => s.Grade)
.Include(s => s.StudentCourses)
.FirstOrDefault();

24. SQL SELECT TOP(1) [s].[StudentId], [s].[DoB], [s].[FirstName],
[s].[GradeId], [s].[LastName], [s].[MiddleName],
[s.Grade].[GradeId], [s.Grade].[GradeName], [s.Grade].[Section]
FROM [Students] AS [s]
LEFT JOIN [Grades] AS [s.Grade] ON [s].[GradeId] = [s.Grade].[GradeId]
WHERE [s].[FirstName] = N'Bill’
ORDER BY [s].[StudentId] Go
SELECT [s.StudentCourses].[StudentId], [s.StudentCourses].[CourseId]
FROM [StudentCourses] AS [s.StudentCourses]
INNER JOIN ( SELECT DISTINCT [t].*
FROM (
SELECT TOP(1) [s0].[StudentId]
FROM [Students] AS [s0]
LEFT JOIN [Grades] AS [s.Grade0] ON [s0].[GradeId] = [s.Grade0].[GradeId]
WHERE [s0].[FirstName] = N'Bill’
ORDER BY [s0].[StudentId] ) AS [t]
) AS [t0] ON [s.StudentCourses].[StudentId] = [t0].[StudentId]
ORDER BY [t0].[StudentId]

25. ORM not OOM
ORM (Object Relational Mapper) not Object-oriented modeling (OOM)

26. entity data model (EDM)
DB Model First
entity data model (EDM)

27. entity data model (EDM)
DB Model First
DB Code First
entity data model (EDM)

28. entity data model (EDM)
DB Model First
DB Code First
Code First
entity data model (EDM)

29. entity data model (EDM)
DB Model First
DB Code First
Code First
entity data model (EDM)

30. transactions with Entity Framework Core

31. using (var transaction = new System.Transactions.
TransactionScope()) {
var database = new DatabaseContext();
var userA = database.Users.Find(1);
var userB = database.Users.Find(2);
userA.Name = "Admin";
database.SaveChanges();
userB.Age = 28;
transaction.Complete(); }

32. var database = new DatabaseContext();
var userA = database.Users.Find(1);
var userB = database.Users.Find(2);
userA.Name = "Admin";
userB.Age = 28;
database.SaveChanges();

33. EF Core features
that help the
DBA

34. string interpolation
in raw SQL

35. string interpolation var city = "Redmond";
using (var context = CreateContext()) {
SELECT *
FROM Customers
WHERE City = {city}"); }

36. SQL string interpolation exec sp_executesql N'SELECT * FROM Customers
WHERE City = nvarchar(4000)’,
@p0=N’Redmond’
SQL

37. string interpolation var citstring description = "Smith";
SqlParameter parameter =
new SqlParameter("LastName", SqlDbType.NVarChar);
parameter.Direction = ParameterDirection.InputOutput;
parameter.Size = description.Length;
parameter.Value = description;y = "Redmond";

38. SQL string interpolation exec sp_executesql N'SELECT * FROM Customers
WHERE City = nvarchar(5)’,
@p0=N’Redmond’
SQL

39. stored procedures var name = "Bill";
var context = new SchoolContext();
var students = context.Students
. FromSqlInterpolated($"GetStudents {name}")
.ToList();

40. query types

41. keyless entity types

42. mapping to views without primary keys

43. mapping to tables without primary keys
mapping to views without primary keys

44. mapping to queries defined in the model
mapping to tables without primary keys
mapping to queries defined in the model
mapping to views without primary keys

45. serving as the return type for FromSql() queries
mapping to tables without primary keys
mapping to queries defined in the model
mapping to views without primary keys
serving as the return type for FromSql() queries

46. keyless entity types
public DbQuery<BlogPostsCount> BlogPostCounts { get; set; }
modelBuilder.Query<BlogPostsCount>().ToView("View_BlogPostCounts")
.Property(v => v.BlogName).HasColumnName("Name");
public class BlogPostsCount {
public string BlogName { get; set; }
public int PostCount { get; set; } }

47. query tags

48. query tags
var albums = _context.Album.Include(a => a.Artist) .TagWith("Description: Query for Albums") .TagWith("Query located: Chinook.Controllers.AlbumsController.Index() method") None");

49. SQL query tags -- Description: Query for Albums
-- Query located: Chinook.Controllers.AlbumsController.Index() method
-- Parameters:
None
SELECT [a].[AlbumId], [a].[ArtistId],
[a].[Title], [a.Artist].[ArtistId], [a.Artist].[Name]
FROM [Album] AS [a]
INNER JOIN [Artist] AS [a.Artist] ON [a].[ArtistId] = [a.Artist].[ArtistId]

50. developer
EF Core features
that help the

51. DbContext Pooling DI container BlogContext BlogContext BlogContext
Request: /blogs/index
scope
BlogContext
blogs controller
blogs controller
scope
BlogContext
Request: /blogs/index
public class BlogsController : Controller {
private BlogContext _context;
public BlogsController(BlogContext context)
_context = context; }
public IActionResult Index()
return _context.Blogs.ToList();
blogs controller
scope
BlogContext
Request: /blogs/index

52. DbContext Pooling DI container BlogContext BlogContext BlogContext
Request: /blogs/index
context pool
scope
BlogContext
blogs controller
BlogContext
BlogContext
BlogContext
Request: /blogs/index
BlogContext
scope
public class BlogsController : Controller {
private BlogContext _context;
public BlogsController(BlogContext context)
_context = context; }
public IActionResult Index()
return _context.Blogs.ToList();
BlogContext
blogs controller
BlogContext
BlogContext
Request: /blogs/index
scope
BlogContext
blogs controller

53. DbContext Pooling DI container BlogContext BlogContext BlogContext
public class BlogsController : Controller {
private BlogContext _context;
public BlogsController(BlogContext context)
_context = context; }
public IActionResult Index()
return _context.Blogs.ToList();
BlogContext
BlogContext

54. DB context pooling
services.AddDbContext<BloggingContext>( options => options.UseSqlServer(connectionString));
services.AddDbContextPool<BloggingContext>( options => options.UseSqlServer(connectionString));

55. demo

56. what you should ask your App Devs?

57. Questions You Should Ask
What is the internal level of support / level of service / expected uptime / RTO for this application?
Are there any dependencies on enterprise edition features of SQL Server?
Are there any other SQL-centric products we need to include in the final architecture?
Is this database storing (or processing) privileged data?
Will there be interfaces to or from other systems in the environment?
What environments need to be created for this solution?
What are the expectations around disaster recovery?

58. what do you want to know as a developer?

59. trust but verify

60. teamwork

61. partnerships

63. Chris Woodruff
Quicken Loans
Thank you!
/chris.woodruff
@cwoodruff