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 <[email protected] <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 [email protected] <javascript:>. > >> To post to this group, send email to [email protected] > <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 [email protected] <javascript:>. > > To post to this group, send email to [email protected] > <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 [email protected]. To post to this group, send email to [email protected]. 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.
