I have connected my Postgres ddbb with django. With inspectdb I have brought all my tables to models.py.
However, I can't find any command for bringing my materialized views to models.py
I have tryed:
python manage.py inspectdb --database=name_ddbb --include-views
But it only gives me the views, not the materialized views.
How can I add automatically the materialized views to django?
Thanks!
Pass the name of the PostgreSQL materialized view as a parameter to the inspectdb call. In my case, it helped.
Note that you'll probably have to make small changes manually in the resulting model code. In particular, indicate that the id field is the primary key.
You can see the detailed example of the PostgreSQL materialized view in Django in this repository.
Working code pieces illustrating the following:
PostgreSQL materialized view in Django.
EagerLoadingMixin in Django REST framework serializer classes to
solve the N+1 queries problem.
Usage of the most generic viewsets.ModelViewSet to build views in
Django REST framework fast and easy.
Advanced PostgreSQL SQL Query with several Common Table Expressions
and JSON functions.
Django post_save and m2m_changed signals.
Related
Let's say that we have a Django app that looks on a legacy database.
If someone make changes on some database tables from a db client as DBeaver for example and not through Django models, is there a way to identify these changes?
You can do in a terminal, inside your Django project directory : python manage.py inspectdb > models.py
You will have models related to your tables.
By default, inspectdb creates unmanaged models. That is, managed = False in the model’s Meta class tells Django not to manage each table’s creation, modification, and deletion.
If you do want to allow Django to manage the table’s lifecycle, you’ll need to change the managed option above to True (or remove it because True is its default value).
I am working on already existing data on relational database. Now question is that how to build models and how to update the tables with new data coming from user (technically django forms)?
Django natively supports creating models for and working with existing data. From the documentation:
Integrating Django with a legacy database
Django will still need to create several of its own tables, but will adapt to use your existing tables. From the doc, you can auto-create models like this:
python manage.py inspectdb > models.py
You'll need to determine whether you want to manage updates to the table structure, but that's getting into details that will be specific to your project.
I spin up a django project. Afterwards, i didn't write models.py but instead I created a database from MySQL command line(independent from django) and created three tables with required columns. Finally i connected my django app with that database successfully. I applied migrations. But now i am confused do i need to write models.py with every field name as in column?
I remember implementing a basic project in which i did write models.py and created database using "python manage.py shell" and then put values using
"from polls.models import Choice, Question"? How do i put data now initially and then using python on some action from UI?
Do i need models.py even for ready made mysql databases?
You do not need to construct models. Some (small) webservers are even completely stateless, and thus do not use a database. But a large part of how Django can help you is based on models.
You can write your own queries, forms, etc. But often by using a ModelForm, Django can for example remove a large amount of boilerplate code. It will make it furthermore less likely that there are mistakes in your code. So although not strictly necessary, the models are usually a keystone in how Django can help you.
You can use the inspectdb [Django-doc] command to inspect the database, and let Django "sketch" the models for you. Usually you will have still some work. Since Django can, for example, not derive that a field is an EmailField, since both a CharField and EmailField look exactly the same at the database side.
You do not need to use inspectdb however. You can construct your own models. If you create your own models, but these exist already at the database side, you might want to set managed = False [Django-doc] in the Meta of your model, to prevent Django from constructing migrations.
I am working on a project that requires connecting to an existing remote Oracle database. the problem is that the client has not given full access to the database. instead i'm only given accesss to some views(Relational Database View) of the database. the table names are not provided.
I'm able to perfrom raw sql queries to the legacydb in my django view.
But it would be very much more easier if i could generate the models for these views and use django ORM. is there any way to accomplish this? What I'm expecting is to use some commands like inspectdb to generate the models from the view provided by the oracle legacy database.
We have a Django application that has been in production since Django 1.1. Over the years, we've manually added bells and whistles to the production PostgreSQL db that weren't at the time overtly supported by Django's db automation, especially in the form of custom indexes.
Django's come a long way since 1.1, and now w/ 1.10 I'm pretty sure the migration framework supports all the custom features we've added manually. Is there any automated tool which will compare a database to the models, and generate migrations to bring the models up to date with the db?
This is built into django, you can just run inspectdb
manage.py inspectdb
Introspects the database tables in the database pointed-to by the NAME setting and outputs a Django model module (a models.py file) to standard output. You may choose what tables to inspect by passing their names as arguments.
Use this if you have a legacy database with which you’d like to use Django. The script will inspect the database and create a model for each table within it.