mygpo/podcasts/migrations/0024_episodes_index.py

   1 # -*- coding: utf-8 -*-
   2
   3
   4 from django.db import migrations
   5
   6
   7 def forward(apps, schema_editor):
   8
   9     # This index can apparently not be created on sqlite
  10     # As it is not recommended for production use, we can just
  11     # skip the index there
  12     if schema_editor.connection.vendor == 'sqlite':
  13         return
  14
  15     migrations.RunSQL(
  16         sql=[
  17             ('CREATE INDEX episodes_podcast_hasreleased '
  18              'ON podcasts_episode '
  19              '(podcast_id, (released IS NOT NULL) DESC, released DESC);',
  20              None)
  21         ],
  22     )
  23
  24
  25 def reverse(apps, schema_editor):
  26     migrations.RunSQL([
  27         ('DROP INDEX IF EXISTS episodes_podcast_hasreleased;', None)
  28     ])
  29
  30
  31 class Migration(migrations.Migration):
  32
  33     dependencies = [
  34         ('podcasts', '0023_auto_20140729_1711'),
  35     ]
  36
  37     operations = [
  38         # Wrap RunSQL in RunPython to check for DB backend
  39         # http://stackoverflow.com/a/37521148/693140
  40         migrations.RunPython(
  41             code=forward,
  42             reverse_code=reverse,
  43         )
  44     ]