How to Use Databases With SQLAlchemy

How to Use Databases With SQLAlchemy - Flask Fridays #8

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Күн бұрын

In this video I'll show you how to use databases with Flask using SQLAlchemy!
Using databases with flask is a little harder than with other web frameworks, but it doesn't have to be too bad if you use SQLAlchemy. I'll show you how in this video by setting up a SQLite database and creating a table, and then adding a form to the site that allows us to add data to the database.
After we learn how to do this with SQLite, we'll learn about MySQL and Postgres.
Timecodes
0:00 - Introduction
1:13 - Pip Install Flask-SQLAlchemy
1:56 - Import SQLalchemy To Our Flask App
2:55 - Set SQLAlchemy Database URI For SQLITE
4:20 - Initialize The Database
4:50 - Create Our Database Model
9:39 - Import Model From The Terminal
10:38 - Create UserForm
11:25 - Create Route And Add_User Function
12:20 - Create Add_User.html Page
13:24 - Add Link To Add_User.html on Navbar
14:22 - Set Form to UserForm in Add_User Function
15:00 - Validate Form On Submit
16:54 - Save Data To Database On Submit
18:50 - Query Database And Output Users To Webpage
21:37 - Style Form With Bootstrap
22:37 - Add Table For User Output
24:46 - Conclusion

Пікірлер: 128

@Codemycom 3 жыл бұрын

▶️ Watch Entire Flask Friday Playlist ✅ Subscribe To My KZfaq Channel: bit.ly/3ig2eJn bit.ly/2IGzvOR ▶️ See More At: ✅ Join My Facebook Group: Codemy.com bit.ly/2GFmOBz ▶️ Learn to Code at Codemy.com ✅ Buy a Codemy T-Shirt! Take $30 off with coupon code: youtube1 bit.ly/2VC9WUN ▶️ Get The Code bit.ly/2L1jBl5

@todorvladimirov1960 3 жыл бұрын

I usually play educational videos at x1.5 speed. I want to thank you for being so thoughtful as to provide it as the default option! Also, great content!

@Codemycom 3 жыл бұрын

Ha glad you enjoyed it!

@witty_name9768 5 ай бұрын

Just want to say that after so long these videos are still helping people learn. Thanks for keeping this series available.

@Codemycom 5 ай бұрын

Welcome!

@SAMIGAMER44 2 жыл бұрын

You really dont know how golden this is

@Codemycom 2 жыл бұрын

Glad you're enjoying it!

@karlduckett 2 жыл бұрын

Awesome! flask-sqlalchemy is great! Thanks for the tutorial!

@Codemycom 2 жыл бұрын

Glad you enjoyed it!

@karthikrajamony6044 3 жыл бұрын

Was waiting for this

@Codemycom 3 жыл бұрын

Glad you like it

@MAAAX2211 2 жыл бұрын

THANK FOR YOUR EFFORT, APPRECIATE IT

@Codemycom 2 жыл бұрын

My pleasure!

@laavanyathanapalan4596 2 жыл бұрын

Thank you soo much. Really helpful!

@Codemycom 2 жыл бұрын

Glad it helped!

@macmohit123 Жыл бұрын

Hi, I am unable to create db.. using db.create_all().... I am getting following error : " This typically means that you attempted to use functionality that needed the current application. To solve this, set up an application context with app.app_context()." ... I have tried to use with function def create_app(): app = Flask(__name__) with app.app_context(): ..., but it doesnt resolve the error.. can you please help

@kendar1193 Жыл бұрын

I think I figured it out: Put this code right below Users class stuff: with app.app_context(): db.create_all() Hope it helps ;)

@TheM4rszal Жыл бұрын

$ python3 >>> from hello import app, db >>> app.app_context().push() >>> db.create_all() >>> exit() OR use command 'flask shell'

@Osiris_fc Жыл бұрын

@@kendar1193 thanks hey. It has been giving me headaches

@renanrivera9805 8 ай бұрын

@@TheM4rszal thanks it works for me

@parthivlakhani3097 Жыл бұрын

Thank You! Please make a Complete Machine Learning Series

@Codemycom Жыл бұрын

Yes

@kristynaherman5737 Жыл бұрын

Hi! This is really great and I am following it for my first flask app project, but I've made my databases + tables in the MySQL workbench and I'm having a lot of trouble connecting the app to my tables (i.e. sending the outputs of my form to the tables initiated in workbench). Would you please add an explanation on how to connect to an existing table (instead of creating one directly in the script)? Thanks a lot!

@wongjowo9152 2 жыл бұрын

Hello, i want to ask about returning the database as string (at 8:58). Could you explain the syntax? Also is it must be self.name?

@diddlybop 3 жыл бұрын

Very helpful! It would've been really helpful to have a larger code window, the panning along with the typing was really not ideal. Maybe there is a reason why you have a zoomed in window, but most tutorials look fine with a full sized window. Thank you for the helpful content! thumbs up.

@Codemycom 3 жыл бұрын

click the expand button on the video player to go fullscreen

@diddlybop 3 жыл бұрын

@@Codemycom ah, I can see how it would seem like I'm talking about the video window, I was referring to your coding editor window in your video. Seeing the entire line of code rather than panning with your typing is what I meant. But it was helpful nonetheless 👏👏👏

@hiwab41 3 жыл бұрын

Thanks 😊

@Codemycom 3 жыл бұрын

Welcome 😊

@scar8d 3 жыл бұрын

sir, not gonna lie, you and Heisenberg(Walter White) look uncannily similar.

@Codemycom 3 жыл бұрын

Ha, I get that a lot...

@elitecoder9246 3 жыл бұрын

Awesome

@Codemycom 3 жыл бұрын

Thanks

@user-oy4bp3bx3o Жыл бұрын

while running the db.create_all() command i got the "RuntimeError: Working outside of application context". please help me out. I have been following along with the Flask Friday since day 1.

@evansmith87 11 ай бұрын

Did you resolve this problem? I am getting the same problem.

@ShivamThakur-pl7ew 4 ай бұрын

from filename import app, db with app.app_context(): db.create_all() it will resolve your issue

@sevii9256 Жыл бұрын

UPDATE I was getting errors when trying to create the database. I put this in my code: with app.app_context(): db.create_all() I added this (for a single run) underneath the class that defined the db.Columns(). I also may have ran db.init_app(app) in between that and the class (or at some point in cmd - importing both db and app), I don't remember where or if that helped or not. Either way, I got it working now (5/5/23)

@Codemycom Жыл бұрын

cool

@witty_name9768 5 ай бұрын

I am just getting into this series now and having the same problem. I can't quite follow your explanation of your solution. Would you be able to point me to a related tutorial or might you remember exactly what you did? Thanks in advance for any help. I've been slogging through google results for a while now.

@officielcesar 2 жыл бұрын

Really great! From the beginning to the end ! Thanks a lot! One thing : I find it a bit hard to follow sometimes because the text is SO BIG ^^ Would be great to dezoom a bit.

@Codemycom 2 жыл бұрын

When I do that, people complain that the text is too small.

@cxl6808 2 жыл бұрын

hello! what if i get an error called AttributeError: 'NoneType' object has no attribute 'is_active' whenever i add my users to the database?

@alanalmeida7887 2 жыл бұрын

Should db.create_all() be executed through the python shell always (to create tables)? Or can we do that in our source code? Because if we deploy the webapp somewhere will we have to explicitly run db.create_all() in the python shell before running the webserver in deployment?

@Codemycom 2 жыл бұрын

You can run commands through the shell from your python file...

@salmantas2335 10 ай бұрын

use this: with app.app_context(): db.create_all() also, I'm not sure of it but you have to use "with" because SQL alchemy requires working Python code

@pandurangasharmaramaka 2 жыл бұрын

When added an email second time, it's not getting added but getting the same message 'User Added Successfully'. What can I do?

@wingielee Жыл бұрын

Hello john. Thank you for your video on flask and other KZfaq videos you have been releasing. However, i have a problem with the initialization and creation of the databse as instructed in this video at time 10:20. When i tried to create my database it kept bringing up the error below; RuntimeError: Working outside of application context. This typically means that you attempted to use functionality that needed the current application. To solve this, set up an application context with app.app_context(). See the documentation for more information. is there anything am not doing right? i"l appreciate your prompt response as usual. Thank you

@Codemycom Жыл бұрын

No idea...google the error and see what you find.

@prethammuthappabs2241 Жыл бұрын

app.app_context().push() add this line to ur code and in the terminal type "from app import app from app import db" it worked for me

@wingielee Жыл бұрын

@@prethammuthappabs2241 thank you bro. I've got it done.. appreciate

@princeakhoury4294 Жыл бұрын

@@prethammuthappabs2241 Where exactly should I write this? I am still getting an error. New to this. Help would really be appreciated! Thanks!

@prethammuthappabs2241 Жыл бұрын

@@princeakhoury4294 the app.app_context thing in ur code down where you try to write ur database name and rest u type in terminal

@DimiEG 3 жыл бұрын

Thanks a lot. Very interesting. Believe PostgreSQL will be the same.

@Codemycom 3 жыл бұрын

Yeah we'll get into postgres soon

@jacquewilson5568 2 жыл бұрын

Great video... is there any good reasons to not suppress the warning with something like this? (newbie here) ? import warnings from sqlalchemy import exc as sa_exc with warnings.catch_warnings(): warnings.simplefilter("ignore", category=sa_exc.SAWarning) # code here...

@rban123 3 жыл бұрын

migrating project to SQLalchemy i found a tool called sqlacodegen which allowed me to convert my entire existing database into a SQLalchemy model in one command

@Codemycom 3 жыл бұрын

fun

@karolinalencina7121 Жыл бұрын

Thank you so much for the tutorial, it helped me a lot at uni! I'm getting an error: File "/Users/karo/Library/Python/3.8/lib/python/site-packages/werkzeug/local.py", line 513, in _get_current_object raise RuntimeError(unbound_message) from None RuntimeError: Working outside of application context. This typically means that you attempted to use functionality that needed the current application. To solve this, set up an application context with app.app_context(). See the documentation for more information. Do you have any suggestions, please? I've tried about 10 stackoverflow answers but nothing works for me. From my research I believe this is an issue that happens because of a recent update to SQLAlchemy?

@Codemycom Жыл бұрын

No idea...you can always use older versions of sqlalchemy. When you pip install it add ==versionNumber to it.

@wackowyatt00 Жыл бұрын

I know this is very old, but if anyone else has the same issue I found a solution. Add the line app.app_context().push() under db = SQLAlchemy(app) In python terminal write: >>>from app import app >>>from app import db >>>db.create_all() That created an instance directory with the database inside.

@akshykumarvaidyanathan8181 Жыл бұрын

@@wackowyatt00 if you are using python shell try >>> from project import app, db >>> app.app_context().push() >>> db.create_all() this worked for me

@moh.abibsafaqdillah2845 5 ай бұрын

thanks bro@@wackowyatt00

@tarunkamra18 2 жыл бұрын

are you installing sql alchemy in virtual environment of flask ? (venv)

@Codemycom 2 жыл бұрын

Yes, the video shows exactly what I'm doing.

@vigramvasi442 2 жыл бұрын

Hello mate, is it possible to move a row up or down in Sqlalchemy?

@Codemycom 2 жыл бұрын

What do you mean?

@srishtijaiswal7079 2 жыл бұрын

Hello sir you have responded to each question so I am expecting the response from your side very soon by today , sir will the database here store on our local server , if yes how can we store it on remote server as I want to deploy my website using heroku

@Codemycom 2 жыл бұрын

Yes it stores local of course. I have videos on using production databases on heroku on the list.