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use existing database instead of django database

i want to connect my existing database of sql server with django but the problem is django has its model which create its own database but i dont want to create database using django i just want to use mine to retrieve data.
the one solution i saw was to use inspectdb but hte problem with inspectdb is that it does not pick wring keys and constraints sometime plus have to set many thing manually but in my project my database is user defined user will connect its database so i dont actually know that how many and what table user's database have do i just want to connect that database with django and use the value of it.
my existing database is sqlserver.
any technique to use my existing database without using django database and retrive data from existing database.
thankyou.

As you mentionned, you should use : inspectdb to create your models as stated in the doc (https://docs.djangoproject.com/en/4.0/howto/legacy-databases/)
Setting the managed option to False in the Meta class of model, you can instruct Django to not make any migrations or database schema modification, but you need to tweak the model yourself to ensure every kind of mapping is as you intendend, and obviousl ensure coherence between your DB schema and models.

Create model for existing database table in django

I have an old table in the database. And I want to create a model in Django application.
After creating a model and I used migrate command then it created a new table with its own name.

Django provides a utility to auto-generate models from an existing database via inspectdb command.
You can create models by introspecting an existing database by executing following command
python manage.py inspectdb
The above command will output all the models Django can create from the existing database to stdout. You can save this as a file by using standard Unix output redirection
python manage.py inspectdb > models.py # or pass the app_name.models.py if you want to generate them inside models.py file of specific app
The output file will be saved to your current directory. Move that file to the correct app and you have a good starting point for further customization.
you can refer https://docs.djangoproject.com/en/4.1/ref/django-admin/#django-admin-inspectdb for more information.

You can specify the table name by setting table on the model's Meta class. Set managed = False to prevent Django from creating the table.
class ExistingModel(models.Model):
...
class Meta:
table = 'existing_table'
managed = False
After making these changes, I would revert the previous migration, remove the migration file, then run makemigrations again.

Creating search form in admin panel - Django

I am new to Django.
I created the sqlite3 database called "test.db" and I'm not using the models.py or default database to sync in views.py for saving data.
I've created the HTML to get the value to store in test.db and print the data using the normal sqlite3 query.
The problem is that I have to access the test.db database in admin panel to search and print the data stored in the database. How to do this task?

You'll need to set up models.py for you to see data in admin functionality of the site. This is because the register statement register(*models, site=django.admin.sites.site) uses the models to display the data. If you are working on legacy database which you aren't, in this case, try this

Django Rebuild all migrations

I am building an app in Django and it uses a live/in-use database.
Basically since the apps development the SQL Database has undergone some structure changes and it is causing issues with Django, Django will try to apply migrations to the database that already exist. For example:
In the Django app I marked the email column as unique which was fine based on the development database. However the main database now always has a table change that marks the email column as unique. Django is fighting this unique key with the one that already exists.
So is it possible to clear all Django migrations and have it make migrations again compared to the more up to date SQL database structure?

If your models are very out of sync with your database, the easiest option is probably to rebuild your models from scratch using inspectdb.
If your models are pretty close to the database already, the first step is to make sure that your models match the database exactly. You can use sqldiff from django-extensions for this.
Once your Django models match your database, follow this answer to re-create migrations based on the existing database schema.

How to change a sqlite table column value type from Django model?

I created a table before I code the Django app and now I merged both the app and the table with following command python manage.py inspectdb > models.py. However after some while I really need to change the value type of one of the column. Is it enough to chage it through the model file or do I need some additional steps?

If you change a field in a Django model, Django itself doesn't know how to update your database accordingly (syncdb only add tables from new models).
You have two options:
manually create your database tables;
use a migration tool like South that detects and generates migration files from changes made to your models;
I recommend the second option as it's programmatic, more error-proof and makes your life easier when you need to go back and forth between database schemas.

There is an easy way to do this. (in Django 2)
After making the necessary changes to the model.py file of your app, run command:
python manage.py makemigrations - This will generate a new file in migration folder of your app.
python manage.py migrate - This will apply those edits on actual databse.
To check if the changes have been applied, run command : .schema <tablename> in your terminal, after entering the sqlite command-line program.