The document discusses the author's experiences and insights on .NET development, particularly the challenges with ORM frameworks like Entity Framework and the advantages of using micro ORMs like Dapper and PetaPoco. It highlights issues such as the object-relational impedance mismatch and introduces NoSQL databases as alternatives, emphasizing event sourcing as a solution to manage data effectively. Additionally, it mentions the persistence of SQL in the context of various data storage approaches and provides resources for further exploration.

1. Not just SQL…
Serhiy Kalinets
Rails Reactor
kalinets@gmail.com
@skalinets
@skalinets 1

2. About Me
16 year in the
business
In .NET since 2005
Love to code
@skalinets 2

3. @skalinets 3

4. .NET
ASP.NET
SQL Server
Entity Framework
@skalinets 4

5. What do all some .NET developers
think about
EF?
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6. @skalinets 6

7. Why Pain
Too much configuration
Leaking abstractions
Object model does not fit business model
Things become complicated very fast
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8. @skalinets 8

9. But we know SQL!
And ORMs treat a custom SQL an
“advanced” feature
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10. Micro ORMs:
the best from both worlds
Handcraft SQL for queries
Handles mapping for you
Require less code (and provide less
functionality)
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11. Dapper
By Stack exchange
Is very fast
Works with POCO and dynamics
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12. PetaPoco
Fast like Dapper
Works with strictly undecorated POCOs, or
attributed almost-POCOs
Built-in paging
SqlBuilder helps create SQL
@skalinets 12

13. Get data
var article1 = db.Single<Article>(123);
var article2 =
db.Single<Article>(
"WHERE ArticleKey = @0", "ART-123");
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14. Modify data
var a = new article();
a.title = "My new article";
...
db.Insert(a);
// Update it
a.content = "Blah blah";
db.Update(a);
// Delete it
db.Delete(a); @skalinets 14

15. Or this way..
db.Delete<article>(
"WHERE article_id=@0",
123);
db.Update<article>(
"SET title=@0 WHERE article_id=@1",
"New Title",
123);
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16. Simple Data
Fun project of @markrendle
Seems to be dead
But still is fun
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17. Simple Data
return Database.Open()
.Users.FindAllByEmail(email)
.FirstOrDefault();
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18. Problems with SQL
It’s kind of old school
Object relational impedance mismatch
Poor scaling out
Schema first
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19. NoSQL
Lot of options
NoSQL == no schema-first
Easy scale / deployment
Something new to give a try…
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20. NoSQL types
Document
Key-value storage
Column Family
Graph
http://nosql-database.org/ lists over 255 DBs
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21. NoSQL: cons
New kid on the block
Almost no analytics
And a lot of others…
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22. But still…
Most approaches store only the current view
Changing things retrospectively == PAIN
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23. Event sourcing to rescue!
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24. ES Concepts
Event is something that has happened
Event can always be applied (no validation
needed)
Events are persisted in event store
Events are available via streams
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25. How it works
Changes in domain trigger events
Entities (aggregates) accept events to update
it’s state
Views (projections) accept events to get
updated as well
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26. Event sourcing
https://msdn.microsoft.com/en-us/library/dn589792.aspx
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27. ES plays nice with CQRS
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28. Benefits
Simple storage for events
Endless choices for projections
Projections can be changed at any time
Maximum data is stored compared to other
models
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29. d60 Cirqus
Simple but powerful event sourcing + CQRS kit
Fluent configuration
Support for multiple storages (MS SQL, Azure
Service Bus, Entity Framework)
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30. Cirqus Focus
Raw performance Polished APIs and general
usefulness
=========================(+)=============
Complex event processing Domain-model-centric
event processing
==========================(+)============
.NET-centric Interoperable
==========(+)============================
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31. NEventStore
Storage agnostic event store
Focus on DDD / CQRS applications
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32. But…
SQL (and MS SQL) are still in the game
There are more than one approaches to SQL
handling
There are more than one approaches to data
storage
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33. And the most important
Don’t try it on work!
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34. Resources
http://www.toptensoftware.com/petapoco/
https://github.com/StackExchange/dapper-dot-net
https://msdn.microsoft.com/en-
us/library/dn589792.aspx (ES)
http://neventstore.org
https://github.com/d60/Cirqus
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