Flask vs MongoDB Which Should Beginners Learn First?

# pip install flask
from flask import Flask

app = Flask(__name__)

@app.route("/")
def home():
    return "Hello from Flask!"

if __name__ == "__main__":
    app.run(debug=True)   # open http://127.0.0.1:5000

// In mongosh (MongoDB shell)
use todo
db.tasks.insertOne({ title: "Learn Flask", done: false })
db.tasks.find({ done: false })

from flask import Flask, jsonify, request

app = Flask(__name__)
tasks = []   # in-memory for now

@app.get("/api/tasks")
def list_tasks():
    return jsonify(tasks)

@app.post("/api/tasks")
def add_task():
    data = request.get_json()
    if not data or not data.get("title"):
        return {"error": "title is required"}, 400
    task = {"id": len(tasks) + 1, "title": data["title"], "done": False}
    tasks.append(task)
    return task, 201

# start the app, then in another terminal:
curl http://127.0.0.1:5000/api/tasks
curl -X POST http://127.0.0.1:5000/api/tasks \
     -H "Content-Type: application/json" \
     -d '{"title": "Read Flask docs"}'

# pip install pymongo   (MongoDB running locally on 27017)
from pymongo import MongoClient

client = MongoClient("mongodb://localhost:27017")
tasks = client["todo"]["tasks"]

tasks.insert_one({"title": "Learn MongoDB", "done": False})
for t in tasks.find({"done": False}):
    print(t["title"])
tasks.update_one({"title": "Learn MongoDB"}, {"$set": {"done": True}})
print(tasks.count_documents({"done": True}))

// mongosh
db.tasks.createIndex({ done: 1 })
db.tasks.find({ done: false }).sort({ title: 1 }).limit(10)

from flask import Flask, request
from pymongo import MongoClient
from bson import ObjectId

app = Flask(__name__)
tasks = MongoClient("mongodb://localhost:27017")["todo"]["tasks"]

def to_json(doc):
    doc["_id"] = str(doc["_id"])
    return doc

@app.get("/api/tasks")
def list_tasks():
    return [to_json(t) for t in tasks.find()]

@app.post("/api/tasks")
def add_task():
    data = request.get_json() or {}
    if not data.get("title"):
        return {"error": "title is required"}, 400
    result = tasks.insert_one({"title": data["title"], "done": False})
    return {"_id": str(result.inserted_id)}, 201

@app.patch("/api/tasks/<task_id>")
def mark_done(task_id):
    tasks.update_one({"_id": ObjectId(task_id)}, {"$set": {"done": True}})
    return {"ok": True}

1. Install Python 3 and MongoDB Community (or use a hosted MongoDB)
2. python -m venv venv  and activate it
3. pip install flask pymongo
4. Save app.py and run: python -m flask --app app run --debug
5. Test with curl or Postman
6. Push to GitHub with a README

Step 1: Python basics - variables, lists, dicts, functions
Step 2: Flask routes and JSON responses (in-memory data)
Step 3: MongoDB in mongosh - insert, find, update, delete
Step 4: PyMongo from Python
Step 5: Connect Flask + MongoDB (this project)
Step 6: Add validation, error handling and tests