Django：加载数据不起作用

Question

I generated a fixture:

python manage.py dumpdata --all > ./mydump.json

I emptied all my databases using:

python manage.py sqlflush | psql mydatabase -U mydbuser

But when i try to use loaddata:

python manage.py loaddata ./mydump.json

I'm recieving this error:

IntegrityError: Could not load tastypie.ApiKey(pk=1): duplicate key 
value violates unique constraint "tastypie_apikey_user_id_key" 
DETAIL:  Key (user_id)=(2) already exists.

I'm having this problem on production and i'm out of ideas. Someone had a similar problem?

Answer 1

First: I believe your unix pipe is incorrectly written.

# 1: Dump your json
$ python manage.py dumpdata --all > ./mydump.json

# 2: dump your schema
$ python manage.py sqlflush > schema.sql

# 3: launch psql
# this is how I launch psql ( seems to be more portable between rhel/ubuntu )
# you might use a bit different technique, and that is ok.

Edited: (very important) Make sure you do not have any active django connections running on your server. Then:

$ sudo -u myuser psql mydatabase

# 4: read in schema
mydatabase=# \i schema.sql
mydatabase=# ctrl-d

# 5: load back in your fixture. 
$ python manage.py loaddata ./mydump.json

Second: If your pipe is ok.. and it might be. Depending on your schema/data you may need to use natural-keys.

# 1: Dump your json using ( -n ) natural keys.
$ python manage.py dumpdata -n --all > ./mydump.json

# followed by steps 2-5 above.

Answer 2

Run loaddata with all @reciever s commented out because they will be fired when loaddata loads your data. If @reciever s create other objects as a sideeffect it will cause collisions.

Answer 3

Jeff Sheffield 的解决方案是正确的，但现在我发现像django-dbbackup这样的解决方案是迄今为止对任何数据库执行此操作的最通用和最简单的方法。

python manage.py dbbackup