Flask sqlalchemy ошибка

Tried running a file with the following imports:

from flask_sqlalchemy import sqlalchemy
from sqlalchemy import create_engine
from sqlalchemy.orm import scoped_session, sessionmaker

Received the following error:

ImportError: No module named 'flask_sqlalchemy'

SQLAlchemy is installed. Still, I tried to reinstall into the directory in which it will be used. I got this:

The directory '/Users/_/Library/Caches/pip/http' or its parent directory is not owned by the current user and the cache has been disabled. Please check the permissions and owner of that directory. If executing pip with sudo, you may want sudo's -H flag.
The directory '/Users/_/Library/Caches/pip' or its parent directory is not owned by the current user and caching wheels has been disabled. check the permissions and owner of that directory. If executing pip with sudo, you may want sudo's -H flag.
Requirement already satisfied: Flask-SQLAlchemy in /Library/Python/2.7/site-packages (2.3.2)
Requirement already satisfied: Flask>=0.10 in /Library/Python/2.7/site-packages (from Flask-SQLAlchemy) (1.0.2)
Requirement already satisfied: SQLAlchemy>=0.8.0 in /Library/Python/2.7/site-packages (from Flask-SQLAlchemy) (1.2.10)
Requirement already satisfied: Jinja2>=2.10 in /Library/Python/2.7/site-packages (from Flask>=0.10->Flask-SQLAlchemy) (2.10)
Requirement already satisfied: itsdangerous>=0.24 in /Library/Python/2.7/site-packages (from Flask>=0.10->Flask-SQLAlchemy) (0.24)
Requirement already satisfied: Werkzeug>=0.14 in /Library/Python/2.7/site-packages (from Flask>=0.10->Flask-SQLAlchemy) (0.14.1)
Requirement already satisfied: click>=5.1 in /Library/Python/2.7/site-packages (from Flask>=0.10->Flask-SQLAlchemy) (6.7)
Requirement already satisfied: MarkupSafe>=0.23 in /Library/Python/2.7/site-packages (from Jinja2>=2.10->Flask>=0.10->Flask-SQLAlchemy) (1.0)

The bit about me not owning the directory is incorrect. I’m the only one on this machine. I own everything.

Anyway, I go back to rerun the file and get the same error message. So, it’s installed, but not installed or, at the very least, not available to me.

One error message I saw when I commented out one of the import statements read as follows:

File "/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/sqlalchemy/engine/strategies.py

I have no clue how to fix this and get SQLAlchemy up and running. I’ve burned over 1.5 hours on it. The last error listed suggests having 2 versions of python may have something to do with it.

Your thoughts on a remedy would be appreciated.

In this tutorial, we will cover how to fix Modulenotfounderror: no module named flask_sqlalchemy error.

Along with we will briefly discuss what are the causes and understand what module is this.

When developing applications with Python, Flask is one of the most popular frameworks to use.

It is simple, lightweight, and provides the essential features needed for web development.

However, when working with Flask, you may encounter an error message that says “ModuleNotFoundError: No module named ‘flask_sqlalchemy’”.

So let’s get started!

Flask-SQLAlchemy is a module for the Flask web framework that provides an easy-to-use interface for working with relational databases using SQLAlchemy.

Additionally, SQLAlchemy is a Python library that provides a high-level, object-oriented interface for working with databases.

Flask-SQLAlchemy allows you to define your database schema using Python classes, and it provides a set of tools for querying, updating, and managing your database data.

It also includes support for advanced features such as migrations, relationships between tables, and database transactions.

What is Modulenotfounderror: no module named ‘flask_sqlalchemy’?

ModuleNotFoundError: No module named ‘sqlalchemy’ is an error in Python that raise when we forget to install the SQLAlchemy module before importing it or installing it in an incorrect environment.

How to fix Modulenotfounderror: no module named ‘flask_sqlalchemy’

Reason why we encounter Modulenotfounderror: no module named ‘flask_sqlalchemy’

Having Modulenotfounderror: no module named ‘flask_sqlalchemy’ is due to the following reasons:

• The SQLAlchemy package was not installed by running pip install SQLAlchemy.
• Installing the package in a Python version other than the one you’re currently using.
• Installing the package on a global scale rather than in your virtual environment.
• The IDE running an incorrect version of Python.
• Naming your module sqlalchemy.py which would shadow the official module.
• Declaring a variable named sqlalchemy which would shadow the imported variable.

If the error continues, acquire your Python version and ensure that you are installing the package with the correct Python version.

Other Solutions in fixing Modulenotfounderror: no module named ‘flask_sqlalchemy’

• The modulenotfound error shows because of the relative imports.
• Having different versions of Python and pip in your system. Try this command to fix:
  • python3 -m pip install sqlalchemy
  • pip3 install sqlalchemy
  • pip install sqlalchemy
• Typically facing server-side issue. Try this command:
  • pip install –user sqlalchemy
• If you are using Ubuntu, an error may appear so use this command:
  • sudo apt install sqlalchemy

Conclusion

In conclusion, Modulenotfounderror: no module named flask_sqlalchemy is an error raised when the Python code is trying to import the “flask_sqlalchemy ” module but it can’t be found.

Either the module is not installed or it’s installed in a location where your Python interpreter is not looking for it.

Remember to always keep your Python installation and modules up to date, and to check for missing dependencies if you encounter any issues.

That’s it we have provided solutions for fixing this error. However, if you follow the steps and encounter any further errors, feel free to ask for more help!

If you are finding solutions to some errors you’re encountering we also have Modulenotfounderror: no module named django_filters.

Go to flask

Когда я получил сообщение: «RuntimeError: Working outside of request context», — я понял, что не внимательно читал документацию. Точнее читал внимательно, но не ту версию. Прочитав нужную версию (ссылка есть в первом сообщении), исправил на:

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with app.app_context():
    db.create_all()

Но, как и изложено выше, упёрся в стену. Ошибки исчезли, но база не создавалась. Разумеется возник закономерный вопрос, что тут все же не так. В документации более ничего не увидел (видимо, плохо смотрел).

Дальнейший ход рассуждений был таким: раз это база данных, то, когда речь идёт о CREATE, INSERT или UPDATE, то тут нужен commit. Попытка решить проблему «в лоб»:

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with app.app_context():
    db.create_all()
    db.commit()

результатов не принесла. В поисках на просторах Web, на Stackoverflow обнаружил одну идею и переписал так:

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with app.app_context():
    db.create_all()  
    db.session.commit()

И база создалась. Причем создалась на втором уровне вложенности: varmain-instancesimple.db.

Начало положено…