This needs to be done in three South migrations to not block users
from sending messages for a long time. Adding the column requires a
write lock on the zephyr_message table and populating the new column
takes a long time. Thus, we can't do them both in the same
transaction (which South forces on migrations). Additionally,
creating the index takes a lot of computation and needs to lock the
table when not done CONCURRENTLY, which can't be done inside of a
transaction.
To do this manual change, you need to run:
python manage.py migrate zephyr 0007
ssh postgres.humbughq.com 'echo "CREATE INDEX CONCURRENTLY zephyr_message_search_tsvector ON zephyr_message USING gin(search_tsvector);" | psql'
python manage.py migrate zephyr 0008
on staging. No action is required on prod since the database is
shared.
Note that this migration must be done completely before we switch to
using the tsvector cache column.
(imported from commit b6a27013a60c1fd196eabb095d2d11d20bba5aac)
Autogenerated schema migration:
+ Added field in_home_view on zephyr.Subscription
To do this manual change, you need to run:
python manage.py migrate zephyr 0005
on staging. No action is required on prod since there is a shared database.
(imported from commit d554f17b25631482ec2d5605a42ac0b9d6df421e)
This schema migration is only for use in automated migrations. To
deploy on the production database (the migration only needs to be
done once for both of staging and prod because they share a
database), you should instead execute the following SQL manually:
$ ssh postgres.humbughq.com
$ psql
humbug=> CREATE INDEX CONCURRENTLY zephyr_message_full_text_idx ON zephyr_message USING gin(to_tsvector('english', subject || ' ' || content));
Note the addition of the "CONCURRENTLY" keyword. The problem is that
creating the index takes non-trivial time and requires a write lock
on the table while the index is being created. This would mean that
users would be unable to send messages while we were generating the
index, which isn't acceptable. We can't create the index
concurrently in the South migration because concurrent index
creations can't happen inside of a transaction and South forces a
transaction on migration functions.
Also note that this index must be created before Postgres full text
search is deployed to the app because full text search without an index
is actually much slower than plain search using the LIKE operator.
(imported from commit 8b9445c27d0e427278de997b22342bffe6d855b7)
Added field invited_at on zephyr.PreregistrationUser, with a one-time
default of Jan 1, 1970 for existing objects.
Added M2M table for streams on zephyr.PreregistrationUser
Deleted unique constraint for ['email'] on zephyr.PreregistrationUser
(imported from commit 85247acb488201f8fc51dfaae354423c27eddcb0)
Zev Benjamin
Luke Faraone
Leo Franchi