SQLAlchemy ORM conversion to pandas DataFrame

Michael Zippo

👻 Check our latest review to choose the best laptop for Machine Learning engineers and Deep learning tasks!

Is there a solution converting a SQLAlchemy <Query object> to a pandas DataFrame?

Pandas has the capability to use pandas.read_sql but this requires use of raw SQL. I have two reasons for wanting to avoid it:

I already have everything using the ORM (a good reason in and of itself) and
I"m using python lists as part of the query, e.g.:

db.session.query(Item).filter(Item.symbol.in_(add_symbols) where Item is my model class and add_symbols is a list). This is the equivalent of SQL SELECT ... from ... WHERE ... IN.

Is anything possible?

👻 Read also: what is the best laptop for engineering students?

SQLAlchemy ORM conversion to pandas DataFrame del: Questions

__del__

How can I make a time delay in Python?

5 answers

I would like to know how to put a time delay in a Python script.

2973

Answer #1

import time
time.sleep(5)   # Delays for 5 seconds. You can also use a float value.

Here is another example where something is run approximately once a minute:

import time
while True:
    print("This prints once a minute.")
    time.sleep(60) # Delay for 1 minute (60 seconds).

2973

Answer #2

You can use the sleep() function in the time module. It can take a float argument for sub-second resolution.

from time import sleep
sleep(0.1) # Time in seconds

SQLAlchemy ORM conversion to pandas DataFrame del: Questions

__del__

How to delete a file or folder in Python?

5 answers

How do I delete a file or folder in Python?

2639

Answer #1

os.remove() removes a file.
os.rmdir() removes an empty directory.
shutil.rmtree() deletes a directory and all its contents.

Path objects from the Python 3.4+ pathlib module also expose these instance methods:

pathlib.Path.unlink() removes a file or symbolic link.
pathlib.Path.rmdir() removes an empty directory.

We hope this article has helped you to resolve the problem. Apart from SQLAlchemy ORM conversion to pandas DataFrame, check other __del__-related topics.

Want to excel in Python? See our review of the best Python online courses 2023. If you are interested in Data Science, check also how to learn programming in R.

By the way, this material is also available in other languages:

Boris Wu

Boston | 2023-04-01

Maybe there are another answers? What SQLAlchemy ORM conversion to pandas DataFrame exactly means?. Will use it in my bachelor thesis

Schneider Jackson

Warsaw | 2023-04-01

io Python module is always a bit confusing 😭 SQLAlchemy ORM conversion to pandas DataFrame is not the only problem I encountered. I am just not quite sure it is the best method

Frank OConnell

Prague | 2023-04-01

Maybe there are another answers? What SQLAlchemy ORM conversion to pandas DataFrame exactly means?. I am just not quite sure it is the best method