Hi Sandeep, A snapshot (or at least a diff from the previous one) is stored when you run makemigrations.
Collin On Wednesday, March 4, 2015 at 2:15:41 PM UTC-5, Murthy Sandeep wrote: > > Hi > > thanks for the info. > > The docs also say that RunPython runs “custom Python code > in a historical context”. What does that mean exactly? It seems > related to the apps and schema_editor arguments passed to > the custom method that will be called by RunPython - is this something > like a snapshot of the app model that is stored when I do `python > manage.py migrate`? > > Sandeep > > > > On 2 Mar 2015, at 19:37, aRkadeFR <con...@arkade.info <javascript:>> > wrote: > > > > Hello, > > > > Indeed, the data migration is the best way. Check out > > the documentation here: > > > https://docs.djangoproject.com/en/1.7/ref/migration-operations/#django.db.migrations.operations.RunPython > > > > > You write your function that will be called by the RunPython > > and will load your JSON. > > Migration are ordered, your first migration will create the > > tables and the second (your data migration) will load your > > JSON. > > > > To create an empty migration: > > ./manage.py makemigrations <app> --empty > > > > You can rename to a useful descriptive name the migration > > file. > > > > Have a good one > > > > > > On 03/02/2015 08:16 AM, Sandeep Murthy wrote: > >> Hi > >> > >> I've tried to get the answer to this question (which is a bit > open-ended) on stackoverflow without much success, which > >> is basically this: what is the recommended approach to populating a > pre-existing Django app database table (generated > >> from a model and which is currently empty) with JSON data? > >> > >> There seem to be several alternatives given in the Django documentation > (Django 1.7 manual) which include (1) fixtures, > >> (2) SQL scripts, (3) data migrations. Of these I am a bit confused by > the advice in the manual which suggests that (1) > >> and (2) are only useful for loading initial data. That's not what I > want to do. The data that the app needs is going to be > >> persistent and permanent because the app is intended to be a web query > tool for a large dataset that is currently in the > >> form of several JSON files, each containing on average thousands of > JSON objects, each object representing an entry > >> corresponding to a table entry in a relational db. The data is not > going to be re-loaded or change after entry, and there > >> is no user facility for changing the data. > >> > >> The table has been created using the makemigrations and migrate tools, > but is empty. I just need to populate the > >> table with the JSON data. It seems that I need to write a custom data > migration script that will insert the data into the > >> table via the interpreter, and then I need to run python manage.py > migrate. Is this the case, and if so, are there > >> are examples that I could use? > >> > >> Thanks in advance for any suggestions. > >> > >> SM > >> -- > >> You received this message because you are subscribed to the Google > Groups "Django users" group. > >> To unsubscribe from this group and stop receiving emails from it, send > an email to django-users...@googlegroups.com <javascript:>. > >> To post to this group, send email to django...@googlegroups.com > <javascript:>. > >> Visit this group at http://groups.google.com/group/django-users. > >> To view this discussion on the web visit > https://groups.google.com/d/msgid/django-users/db5919c5-ace4-4556-b90e-aa47baa26552%40googlegroups.com. > > > >> For more options, visit https://groups.google.com/d/optout. > > > > > > -- > > You received this message because you are subscribed to the Google > Groups "Django users" group. > > To unsubscribe from this group and stop receiving emails from it, send > an email to django-users...@googlegroups.com <javascript:>. > > To post to this group, send email to django...@googlegroups.com > <javascript:>. > > Visit this group at http://groups.google.com/group/django-users. > > To view this discussion on the web visit > https://groups.google.com/d/msgid/django-users/54F42164.6040505%40arkade.info. > > > > For more options, visit https://groups.google.com/d/optout. > > -- You received this message because you are subscribed to the Google Groups "Django users" group. To unsubscribe from this group and stop receiving emails from it, send an email to django-users+unsubscr...@googlegroups.com. To post to this group, send email to django-users@googlegroups.com. Visit this group at http://groups.google.com/group/django-users. To view this discussion on the web visit https://groups.google.com/d/msgid/django-users/d78e387b-9232-4a5a-b6d5-1306b5084913%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
