Fun with Django and Databases

A talk I gave at EuroPython 2010

Transcript

1. Django and Databases
   Fun with
   

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2. ""Andrew speaks English
   like a machine gun
   speaks bullets.""
   Reinout van Rees
   

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3. Introduction
   

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4. from django.db import models
   

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5. First, an aside
   

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6. ""When all you have is a
   hammer, everything
   looks like a nail""
   Abraham Manslow (paraphrased)
   

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7. Also, "NoSQL"? Really?
   

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8. queryset.raw()
   

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9. qs = Teacher.objects.raw("""
   SELECT t.name, COUNT(s.id)
   FROM school_teacher AS t
   INNER JOIN school_student AS s
   ON t.id = s.teacher_id
   GROUP BY t.name
   HAVING COUNT(s.id) > 2
   """)
   

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10. queryset.aggregate()
    

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11. qs = Teacher.objects.annotate(
    num_students =
    models.Count('student')
    ).filter(num_students__gt=2)
    

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12. Search
    haystack __search=
    

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13. Schema Changes
    

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14. Changing Requirements
    

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15. Dynamic/Unknown Data
    

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16. Document Databases
    MongoDB
    CouchDB
    

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17. Key-Value Stores
    Redis
    Cassandra
    

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18. Redis
    Sets Sorted Sets Hashes
    Pub/Sub Atomicity
    

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19. Message Queues
    AMQP
    Celery
    

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20. Various Others
    Graph databases
    Filesystems
    VCSs
    

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21. Conclusion
    

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22. Thanks.
    Andrew Godwin
    @andrewgodwin
    http://aeracode.org
    

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