Gotta Persist 'Em All: Realm as Replacement for SQLite

Realm is a new player on mobile database scene, and acts as a replacement for SQLite on Android and Core Data on iOS by providing a database and an easy-to-use object-relational mapping-like interface. Learn how to use it in your own projects and how it compares to working with SQLite in a beginner-friendly sample app with Pokémon.

Transcript

1. Gotta Persist ‘Em All:
   Realm as Replacement
   for SQLite
   Siena Aguayo
   Indiegogo
   @sienatime
   

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2. Overview
   ● What Realm Is
   ● Pros and cons
   ● Compare and contrast with SQLite
   ● What Realm Isn’t
   

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3. But First, Hello!
   

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7. What Realm Is
   

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8. ● “embedded mobile database”
   Realm
   ● Core is written in C++
   ● Available for Android and iOS
   ● Second most-deployed mobile database in
   the world
   

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9. Pros
   

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10. Pros for Realm
    ● Very responsive team
    ● Easy to use
    ● Convenient for creating and storing data on
    the fly
    ● Object conversion handled for you
    ● Faster than SQLite
    

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11. Source: http://www.slideshare.net/ChristianMelchior/realm-building-a-mobile-database#25
    

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12. Cons
    

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13. Cons for Realm
    ● Have to create with Java on the device
    ● Still under active development
    ● Not a lot of content online
    ● No importing
    ● Can’t access objects across threads
    

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14. Missing Features
    ● Auto-incrementing ids
    ● Compound primary keys
    ● Testing with Robolectric
    ● Map support
    

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15. Compare and Contrast with SQLite
    

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16. Database Connection
    and Setup
    

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17. Shipping with Existing Database
    copy
    SQLite: SQLiteAssetHelper
    Realm: Sample migration app
    

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18. Shipping with Existing Database
    SQLite:
    dbHelper.getReadableDatabase() or
    dbHelper.getWritableDatabase()
    Realm:
    Realm.getDefaultInstance()
    

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19. Creating Schema
    SQLite
    

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20. Creating Schema
    Realm
    

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21. In Realm, your models ARE your schema.
    

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22. Reading Data
    

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23. Java with SQLite
    

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24. Find All
    Java with Realm
    Find First
    

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25. Writing Data
    

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26. Java with SQLite
    

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27. Java with Realm
    

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28. Java with Realm
    

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29. Adding Relationships and
    Complex Queries
    

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30. Encounter has a LocationArea
    LocationArea has a Location
    

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31. Location
    LocationArea
    Encounter
    

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32. Raw SQL
    

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33. Java with Realm
    

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35. What Realm Isn’t
    

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36. Realm says they are not an ORM because
    your data is not copied.
    

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37. An ORM or not?
    SQLite
    >> pragma table_info(pokemon)
    0|id|INTEGER|1||1
    1|identifier|VARCHAR(79)|1||0
    2|height|INTEGER|1||0
    3|weight|INTEGER|1||0
    Java
    public class Pokemon {
    private int id;
    private String identifier;
    private int height;
    private int weight;
    // constructor(s),
    // getters, setters
    }
    Typical ORM usage
    

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38. Data from Realm in the toString()...
    Member variables are all uninitialized...
    

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39. Shout-Out to Other ORMs
    ● greenDAO
    ● Active Android
    ● Sugar ORM
    ● ORMLite (Java)
    ● Cupboard
    Michael Pardo’s Android Data talk
    

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40. Conclusion
    

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41. Acknowledgments
    ● Realm: http://realm.io/
    ● SQLite db from veekun’s Pokémon repo:
    https://github.com/veekun/pokedex
    ● Official Pokémon art by Ken Sugimori
    ● Christian Melchior for feedback
    

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42. Questions?
    Twitter: @sienatime
    

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