Lazy IITians – Viva Prep

See reviews Level3_24 MAD1 Level 3

Aug 14, 2026

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1

Rate your app on the basis of how your viva went and justify it. some more theories ques which all were from this sheet only (it seems like he also have a sheet from which he is asking questions 🤡) As some others said above he is very rude; and HE IS. He tried to roast me twice during the viva lol. As the viva started he said " show me your ID card" in a very rude manner. He was impolite from the start. The trick is to pretend like you are very innocent and a good listener. Let him complete his entire question and wait for 1-2 sec and then respond also have a very serious face all the time like you are thinking about how to answer or solve his question I did this and in the end, he praised me for my good behaviour 🤡.

Times asked 1

Official solution

SimpleCamera pe clearly college/IITM ID dikhao — naam aur photo match hone chahiye.
Viva tipPehle se ID haath mein rakho, glare mat aane do. Iske baad GitHub + project run.

See reviews Level3_24 MAD1 Level 3

Aug 14, 2026

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1

Viva went well. Based on feedback from other students, I had already:

Times asked 2

Official solution

SimpleViva wrap-up hai. Short thanks + confirm submission ZIP latest hai.
2

Kept student id open for review

Times asked 2

Official solution

SimpleCamera pe clearly college/IITM ID dikhao — naam aur photo match hone chahiye.
Viva tipPehle se ID haath mein rakho, glare mat aane do. Iske baad GitHub + project run.
3

Kept viva-workflow portal open for downloading my code Viva was for 35-40 minutes and covered the following:

Times asked 2

Official solution

SimpleExaminer portal wala submitted ZIP chahta hai. Local extra changes mat dikhana.
Suggested flow1) Portal ZIP download
2) Extract
3) venv + pip install -r requirements.txt
4) flask run / python app.py
4

15 minutes for running the demo

Times asked 2

Official solution

SimpleDemo script pehle se practice: 5–7 min, Admin + User roles, saare mandatory features.
Suggested flow1) Register/login user
2) Admin login — CRUD
3) Approval/blacklist
4) Booking/apply + edge case
5) Search
6) Logout
Viva tipBolte-bolte dikhao. Code tab kholna jab poochhein.
5
Move the search bar to the bottom

Times asked 2
Official solution

SimpleSearch: form/query param → ilike filter → results template.
Example
```
q = request.args.get('q', '').strip()
lots = Lot.query.filter(Lot.name.ilike(f'%{q}%')).all()
```
6

What is caching?

Times asked 23

Official solution

SimpleCache baar-baar DB/compute na karne ke liye result yaad rakhta hai.
Browser cache, Flask cache, Redis. Example: dashboard counts 30 sec Redis mein.
Cookies alag (client data). HTTP 304 Not Modified bhi cache related.
MAD1 mein optional. Scale poochhe to pehle indexes + cache, phir extra servers.
7

What is AJAX?

Times asked 4

Official solution

SimpleAJAX page reload ke bina server se data laata hai. Aaj kal fetch() + Promises.
fetch('/api/users').then(r => r.json()).then(data => { ... })
Promise: future value (pending/fulfilled/rejected). fetch Promise return karta hai.
SPA (Vue): ek HTML, baaki routes JS se, partial update. MAD1 generally full page render (Jinja) — submit pe poora refresh.
async/await Promise ka clean syntax.
8

All questions were from this sheet itself, so revise thoroughly before the viva and you will do well Overall the viva went well. Seems like the proctor wants people to be honest and straightforward with him. If one does that, he is flexible with everything. For e.g., I downloaded the MAD-1 project from the portal instead of MAD-2. The project didn't run and I was shitting bricks, but he was quite calm and gave me enough time to figure out that I have downloaded MAD-1 and not MAD-2. I corrected this error and he continued like nothing had happened.

Times asked 2

Official solution

SimpleExaminer portal wala submitted ZIP chahta hai. Local extra changes mat dikhana.
Suggested flow1) Portal ZIP download
2) Extract
3) venv + pip install -r requirements.txt
4) flask run / python app.py

See reviews Level3_11 MAD1 Level 3

Aug 14, 2026

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1

Checksum

Times asked 5

Official solution

SimpleExaminer wohi ZIP chahta hai jo tumne submit kiya, local extra magic nahi.
Portal download → extract → redis, venv, pip, npm, flask, worker, beat.
Checksum maange to hash. Uncommitted files mat dikhana.
Examiner 2 cheezein: simple desi line + tumhare project ki exact file.
Pehle ID, GitHub, portal ZIP. Phir run: Redis + Flask + worker + beat + Vue. Feature demo: login, RBAC, cache hit/miss, Celery mail, search.
Line pe ungli: input kahan, kaunsa check, query/cache/task, JSON/UI. Copilot band. Jo nahi kiya honestly bolo + kaise add karte.
Suggested flow1) ZIP
2) Extract
3) Redis + venv + pip
4) npm/vite
5) flask + celery worker + beat
Project example: Submitted zip run. README commands copy.
Viva tipChecksum maange to hash match karke dikhao. Extra uncommitted files mat dikhana.
2
Start the App

Times asked 2
Official solution

Simplevenv activate → dependencies → DB create/migrate → flask run. Browser pe localhost dikhao.
Example
```
python -m venv .venv
source .venv/bin/activate
pip install -r requirements.txt
flask run
```
3

Demo of Librarian screen

Times asked 2

Official solution

SimpleDemo script pehle se practice: 5–7 min, Admin + User roles, saare mandatory features.
Suggested flow1) Register/login user
2) Admin login — CRUD
3) Approval/blacklist
4) Booking/apply + edge case
5) Search
6) Logout
Viva tipBolte-bolte dikhao. Code tab kholna jab poochhein.
4
How the Book and Sections models are implemented

Times asked 2
Official solution

Simplemodels.py = har table ki class: columns, PK/FK, relationships. Yeh Model layer hai.
Suggested flow1) Classes list karo
2) Har table ka kaam 1 line
3) Relationships (1-M / M-M)
4) Constraints (unique, nullable)
Example
```
class Lot(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    name = db.Column(db.String(80), nullable=False)
    spots = db.relationship('Spot', backref='lot', lazy=True)
```
5

How rating is updated in the backend

Times asked 2

Official solution

SimpleCode explain formula: input kya aaya → auth/validation → DB change → response/UI.
Viva tipFunction signature + 3-4 important lines + edge case.
6
Authentication, Authorization

Times asked 1
Official solution

SimpleAuthentication: tu kaun hai? (login). Authorization: tujhe permission hai? (role check).
Example
```
# auth
if check_password_hash(user.password, pwd):
    session['user_id'] = user.id

# authz
if user.role != 'admin':
    abort(403)
```
7
Gave Good inputs on how the UI can be made better and the general end user expectations from a UI

Times asked 2
Official solution

SimplePehle 1-line definition, phir apne MAD1 project mein file dikhao, phir chhota example.
Suggested flow1) Concept kya hai?
2) Mere code mein kahan?
3) Example / demo
4) Edge case
Example
```
# related file: models.py / routes / template
# formula: request → check/auth → DB → render/redirect
```
Viva tipExact line yaad nahi to honestly related part dikhao. Bluff mat karo.

See reviews Level3_11 MAD1 Level 1

Aug 14, 2026

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1

Demo of the app.

Times asked 1

Official solution

SimpleDemo script pehle se practice: 5–7 min, Admin + User roles, saare mandatory features.
Suggested flow1) Register/login user
2) Admin login — CRUD
3) Approval/blacklist
4) Booking/apply + edge case
5) Search
6) Logout
Viva tipBolte-bolte dikhao. Code tab kholna jab poochhein.
2

Lazy loading.

Times asked 1

Official solution

Simplelazy loading: related objects kab load hon. lazy=True default (access pe query). joined/eager pehle se join.
3
Left join(from dbms).

Times asked 1
Official solution

SimpleJOIN related tables ek result mein. Inner = match only; left = left side sab + match.
Example
```
db.session.query(Booking, User).join(User).filter(User.id == uid).all()
```
4

Delete vs truncate.

Times asked 2

Official solution

SimpleUngli rakhe to 4-line formula — panic ki jagah structure.
1) File ka role: model / Flask route / Vue SFC / celery task / config
2) Input kahan: JSON, params, token, props, $route
3) Kya kaam: query, cache, validation, .delay()
4) Output: jsonify, this.items, email, redirect
Unknown keyword: import, decorator, if, commit — har ka reason. Bluff mat.
Suggested flow1) Kaunsi layer?
2) Input?
3) DB/cache/task?
4) Response/UI?
Project example: Booking POST: jwt, seats check, commit, 201, Vue list push.
Viva tipUnknown keyword: import, decorator, if, commit — har ka reason. Panic mat.
5

Single page applications.

Times asked 1

Official solution

SimpleMAD1 typical: Browser → Flask routes → validate/auth → SQLAlchemy → SQLite → Jinja response.
Suggested flowRequest → Route → Auth check → DB → render_template / redirect
6

Child components.

Times asked 2

Official solution

SimpleParent-child: parent template mein child component. Props parent→child, emit child→parent.
7

( The proctor was very calm and helpful ,when I was stuck at a point , he suggested me how to do it.)

Times asked 2

Official solution

SimpleViva wrap-up hai. Short thanks + confirm submission ZIP latest hai.

See reviews Level3_24 MAD1 Level 1

Aug 14, 2026

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1

- demonstration

Times asked 1

Official solution

SimpleDemo script pehle se practice: 5–7 min, Admin + User roles, saare mandatory features.
Suggested flow1) Register/login user
2) Admin login — CRUD
3) Approval/blacklist
4) Booking/apply + edge case
5) Search
6) Logout
Viva tipBolte-bolte dikhao. Code tab kholna jab poochhein.
2
- remove bg image and add white colour instead

Times asked 2
Official solution

SimpleLive UI change: relevant CSS/HTML template kholo — color, margin, flex, bootstrap class. Save + hard refresh.
Example
```
/* button red */
.btn-primary { background: red; }

/* center navbar item */
.navbar { justify-content: center; }
```
Viva tipDevTools se pehle try, phir file mein permanent change.
3
- change button colour

Times asked 2
Official solution

SimpleLive UI change: relevant CSS/HTML template kholo — color, margin, flex, bootstrap class. Save + hard refresh.
Example
```
/* button red */
.btn-primary { background: red; }

/* center navbar item */
.navbar { justify-content: center; }
```
Viva tipDevTools se pehle try, phir file mein permanent change.
4
- move navbar to bottom

Times asked 1
Official solution

SimpleLive UI change: relevant CSS/HTML template kholo — color, margin, flex, bootstrap class. Save + hard refresh.
Example
```
/* button red */
.btn-primary { background: red; }

/* center navbar item */
.navbar { justify-content: center; }
```
Viva tipDevTools se pehle try, phir file mein permanent change.
5
- explain models

Times asked 1
Official solution

Simplemodels.py = har table ki class: columns, PK/FK, relationships. Yeh Model layer hai.
Suggested flow1) Classes list karo
2) Har table ka kaam 1 line
3) Relationships (1-M / M-M)
4) Constraints (unique, nullable)
Example
```
class Lot(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    name = db.Column(db.String(80), nullable=False)
    spots = db.relationship('Spot', backref='lot', lazy=True)
```
6
- make any change in db

Times asked 2
Official solution

SimpleDB dikhao: SQLite browser / flask shell se tables. Users, roles, sample rows.
Example
```
flask shell
>>> from models import User
>>> User.query.count()
```
7

- explain entire back+front code

Times asked 2

Official solution

SimpleCode explain formula: input kya aaya → auth/validation → DB change → response/UI.
Viva tipFunction signature + 3-4 important lines + edge case.
8

- inline vs internal css

Times asked 1

Official solution

SimpleUngli rakhe to 4-line formula — panic ki jagah structure.
1) File ka role: model / Flask route / Vue SFC / celery task / config
2) Input kahan: JSON, params, token, props, $route
3) Kya kaam: query, cache, validation, .delay()
4) Output: jsonify, this.items, email, redirect
Unknown keyword: import, decorator, if, commit — har ka reason. Bluff mat.
Suggested flow1) Kaunsi layer?
2) Input?
3) DB/cache/task?
4) Response/UI?
Project example: Booking POST: jwt, seats check, commit, 201, Vue list push.
Viva tipUnknown keyword: import, decorator, if, commit — har ka reason. Panic mat.
9

- rate app and justify

Times asked 2

Official solution

SimpleApp rate 1–5 honestly + reason: completeness, UI, edge cases. Weak points improve plan ke saath bolo.
10

- buh-bye

Times asked 2

Official solution

SimpleViva wrap-up hai. Short thanks + confirm submission ZIP latest hai.
11

- good luck!

Times asked 2

Official solution

SimpleEnd of viva note — kuch extra nahi. Agar time bache to ek unique feature highlight karo.

See reviews Level2_101 MAD1 Level 2

Aug 14, 2026

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1

Proctor was a chill person, probably kept on increasing difficulty of questions because I kept answering.

Times asked 2

Official solution

SimpleViva wrap-up hai. Short thanks + confirm submission ZIP latest hai.
2
2) went through models

Times asked 2
Official solution

Simplemodels.py = har table ki class: columns, PK/FK, relationships. Yeh Model layer hai.
Suggested flow1) Classes list karo
2) Har table ka kaam 1 line
3) Relationships (1-M / M-M)
4) Constraints (unique, nullable)
Example
```
class Lot(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    name = db.Column(db.String(80), nullable=False)
    spots = db.relationship('Spot', backref='lot', lazy=True)
```
3

BACKEND

Times asked 2

Official solution

SimpleViva wrap-up hai. Short thanks + confirm submission ZIP latest hai.
4
what is __repr__ (w.r.t. models)?

Times asked 2
Official solution

Simplemodels.py = har table ki class: columns, PK/FK, relationships. Yeh Model layer hai.
Suggested flow1) Classes list karo
2) Har table ka kaam 1 line
3) Relationships (1-M / M-M)
4) Constraints (unique, nullable)
Example
```
class Lot(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    name = db.Column(db.String(80), nullable=False)
    spots = db.relationship('Spot', backref='lot', lazy=True)
```
5

__repr__ vs __str__

Times asked 2

Official solution

SimpleUngli rakhe to 4-line formula — panic ki jagah structure.
1) File ka role: model / Flask route / Vue SFC / celery task / config
2) Input kahan: JSON, params, token, props, $route
3) Kya kaam: query, cache, validation, .delay()
4) Output: jsonify, this.items, email, redirect
Unknown keyword: import, decorator, if, commit — har ka reason. Bluff mat.
Suggested flow1) Kaunsi layer?
2) Input?
3) DB/cache/task?
4) Response/UI?
Project example: Booking POST: jwt, seats check, commit, 201, Vue list push.
Viva tipUnknown keyword: import, decorator, if, commit — har ka reason. Panic mat.
6

what are dunder methods?

Times asked 1

Official solution

SimpleDunder __name__ special. __init__ __repr__ __tablename__. _private convention not encryption.
Why underscores in Python. Dunder methods.
Pehle 1-line definition, phir related MAD2 layer (Vue SFC / Flask route / models.py / tasks.py / Redis).
4-line formula: input kahan se aaya, auth/validation kaunsa, DB ya cache ya Celery, kya return.
Related mix mat karo — cache ≠ Celery, authentication ≠ authorization, v-if ≠ v-show, Beat ≠ Worker. Follow-up ke liye ek difference ready rakho.
Project example: if __name__ == '__main__'.
7
what are decorators?

Times asked 2
Official solution

Simplelogin_required jaisa decorator protected routes pe: session nahi to login redirect.
Example
```
def login_required(fn):
    @wraps(fn)
    def wrapper(*a, **k):
        if 'user_id' not in session:
            return redirect(url_for('auth.login'))
        return fn(*a, **k)
    return wrapper
```
8
write hello world decorator

Times asked 1
Official solution

Simplelogin_required jaisa decorator protected routes pe: session nahi to login redirect.
Example
```
def login_required(fn):
    @wraps(fn)
    def wrapper(*a, **k):
        if 'user_id' not in session:
            return redirect(url_for('auth.login'))
        return fn(*a, **k)
    return wrapper
```
9
cache.memoize vs cache.cached

Times asked 1
Official solution

Simplecached poori view ko yaad rakhta hai, memoize function ke arguments ke hisaab se.
@cache.cached URL / key_prefix (optional query_string) se key banata hai — list endpoints ke liye.
@cache.memoize arguments se key banata hai — get_user(5) aur get_user(9) alag cache.
Prefix clash se galat data mil sakta hai. Dono ka timeout same idea hai. Invalidation: delete_memoized(fn, args) vs cache.delete(prefix).
Example
```
@cache.cached(timeout=30, key_prefix='home')
def home(): ...

@cache.memoize(30)
def get_user(user_id): ...  # alag key per user_id
```
Project example: Venues list = cached. User-wise report function = memoize(user_id).
Viva tipList endpoint: cached. Function with arguments: memoize. Prefix alag rakho warna clash.
10
POST vs PUT vs PATCH

Times asked 1
Official solution

SimplePOST naya janam (har baar naya id). PUT poori photo replace. PATCH sticker chipkao.
POST create, not idempotent. PUT full update, idempotent. PATCH partial.
POST ki jagah PUT se REST semantics toot. GET typically no body.
CRUD map: POST create, GET read, PUT/PATCH update, DELETE delete.
Pehle 1-line definition, phir related MAD2 layer (Vue SFC / Flask route / models.py / tasks.py / Redis).
4-line formula: input kahan se aaya, auth/validation kaunsa, DB ya cache ya Celery, kya return.
Related mix mat karo — cache ≠ Celery, authentication ≠ authorization, v-if ≠ v-show, Beat ≠ Worker. Follow-up ke liye ek difference ready rakho.
Example
```
POST /api/venues
PUT  /api/venues/1   {all fields}
PATCH /api/venues/1 {only name}
```
Project example: POST /api/venues create. PUT /venues/1 saari fields. PATCH sirf name.
11
what is Exception handling, and have you used it? Show

Times asked 1
Official solution

Simpletry/except. Catch Exception not BaseException (SystemExit). IntegrityError 404 abort.
Exception handling. Types ValueError TypeError KeyError IntegrityError HTTPException.
Pehle 1-line definition, phir related MAD2 layer (Vue SFC / Flask route / models.py / tasks.py / Redis).
4-line formula: input kahan se aaya, auth/validation kaunsa, DB ya cache ya Celery, kya return.
Related mix mat karo — cache ≠ Celery, authentication ≠ authorization, v-if ≠ v-show, Beat ≠ Worker. Follow-up ke liye ek difference ready rakho.
Example
```
try:
    db.session.commit()
except IntegrityError:
    db.session.rollback()
    return jsonify(msg='duplicate'), 400
```
Project example: commit except rollback 400.
12

what are different types of exceptions in python?

Times asked 1

Official solution

SimpleValueError TypeError KeyError IntegrityError HTTPException. Specific catch.
Different types of exceptions.
Pehle 1-line definition, phir related MAD2 layer (Vue SFC / Flask route / models.py / tasks.py / Redis).
4-line formula: input kahan se aaya, auth/validation kaunsa, DB ya cache ya Celery, kya return.
Related mix mat karo — cache ≠ Celery, authentication ≠ authorization, v-if ≠ v-show, Beat ≠ Worker. Follow-up ke liye ek difference ready rakho.
Project example: Name 3 you used.
Project example: Name 3 you used.
13
what is the base class of Exceptions

Times asked 1
Official solution

Simple:class object/array/string dynamic CSS.
Purpose dynamic class. Error red.
Directives Vue ke special attributes hain — HTML ko superpower: v-if/v-show, v-for, v-bind (:), v-on (@), v-model.
v-if DOM se hataata/jodta. v-show sirf CSS display. Rare/permission: v-if. Bar-bar toggle: v-show. v-model two-way form. v-bind one-way JS→attribute.
:key v-for pe zaroori warna Vue galat reuse. v-html XSS. Secret UI ke liye sirf v-if kaafi nahi — API 403 bhi.
MAD1 Jinja server HTML. MAD2 yeh directives browser mein reactive.
Example
```
<div :class="{ 'text-danger': error, 'fw-bold': important }">Msg</div>
```
Project example: :class="{ 'text-danger': error }"
14

400 vs 401 status code

Times asked 2

Official solution

SimpleStatus code server ka result: 200 OK, 302 redirect, 400 bad input, 401/403 auth, 404 not found, 500 server error.
15

webhook vs websocket

Times asked 2

Official solution

SimpleUngli rakhe to 4-line formula — panic ki jagah structure.
1) File ka role: model / Flask route / Vue SFC / celery task / config
2) Input kahan: JSON, params, token, props, $route
3) Kya kaam: query, cache, validation, .delay()
4) Output: jsonify, this.items, email, redirect
Unknown keyword: import, decorator, if, commit — har ka reason. Bluff mat.
Suggested flow1) Kaunsi layer?
2) Input?
3) DB/cache/task?
4) Response/UI?
Project example: Booking POST: jwt, seats check, commit, 201, Vue list push.
Viva tipUnknown keyword: import, decorator, if, commit — har ka reason. Panic mat.
16
session vs cookies

Times asked 2
Official solution

SimpleMAD1 mein usually session-based auth: login pe session['user_id'], har request pe verify.
Example
```
session['user_id'] = user.id
uid = session.get('user_id')
user = User.query.get(uid)
```
Viva tipSECRET_KEY set karo warna session insecure. logout pe session.clear().
17

FRONTEND

Times asked 2

Official solution

SimpleMAD1 frontend usually Jinja templates + HTML/CSS/Bootstrap (+ thoda JS). MAD2 pe Vue ho to clearly bolo.
18
what are routes and how are you using them?

Times asked 2
Official solution

SimplePehle 1-line definition, phir apne MAD1 project mein file dikhao, phir chhota example.
Suggested flow1) Concept kya hai?
2) Mere code mein kahan?
3) Example / demo
4) Edge case
Example
```
# related file: models.py / routes / template
# formula: request → check/auth → DB → render/redirect
```
Viva tipExact line yaad nahi to honestly related part dikhao. Bluff mat karo.
19

There were probably a few more, I dont remember right now.

Times asked 2

Official solution

SimpleViva wrap-up hai. Short thanks + confirm submission ZIP latest hai.
20
He seemed to be going with the flow, asked questions from what all you showed him. Counter questions if he feels that you have some lack of clarity in your answers.

Times asked 2
Official solution

SimplePehle 1-line definition, phir apne MAD1 project mein file dikhao, phir chhota example.
Suggested flow1) Concept kya hai?
2) Mere code mein kahan?
3) Example / demo
4) Edge case
Example
```
# related file: models.py / routes / template
# formula: request → check/auth → DB → render/redirect
```
Viva tipExact line yaad nahi to honestly related part dikhao. Bluff mat karo.
21

Good Luck!

Times asked 2

Official solution

SimpleEnd of viva note — kuch extra nahi. Agar time bache to ek unique feature highlight karo.

See reviews Level3_11 MAD1 Level 1

Aug 14, 2026

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Copy set link

1

The viva was between easy to moderate.

Times asked 2

Official solution

SimpleViva wrap-up hai. Short thanks + confirm submission ZIP latest hai.
2

The proctor first asked to demonstrate the app, then asked some questions from app(mostly core functionalities, even sometimes deep functionalities)

Times asked 2

Official solution

SimpleDemo script pehle se practice: 5–7 min, Admin + User roles, saare mandatory features.
Suggested flow1) Register/login user
2) Admin login — CRUD
3) Approval/blacklist
4) Booking/apply + edge case
5) Search
6) Logout
Viva tipBolte-bolte dikhao. Code tab kholna jab poochhein.
3
Most of the questions were repeated from before like:

Times asked 2
Official solution

SimplePehle 1-line definition, phir apne MAD1 project mein file dikhao, phir chhota example.
Suggested flow1) Concept kya hai?
2) Mere code mein kahan?
3) Example / demo
4) Edge case
Example
```
# related file: models.py / routes / template
# formula: request → check/auth → DB → render/redirect
```
Viva tipExact line yaad nahi to honestly related part dikhao. Bluff mat karo.
4
What is Lazy loading?

Times asked 1
Official solution

Simplelazy loading related objects tab load karta hai jab attribute access karte ho, pehle nahi.
```
user = User.query.get(1)  # posts query nahi
```
user.posts # ab query
lazy=True / 'select' default. lazy='joined' eager join. lazy='dynamic' query object.
uselist=False One-to-One (single object, list nahi). Hataoge to list mil sakti hai.
Frontend lazy loading images alag cheez hai (viewport mein aaye tab load).
5
What is the difference between PATCH, PUT and POST?

Times asked 1
Official solution

SimplePOST naya janam (har baar naya id). PUT poori photo replace. PATCH sticker chipkao.
POST create, not idempotent. PUT full update, idempotent. PATCH partial.
POST ki jagah PUT se REST semantics toot. GET typically no body.
CRUD map: POST create, GET read, PUT/PATCH update, DELETE delete.
Pehle 1-line definition, phir related MAD2 layer (Vue SFC / Flask route / models.py / tasks.py / Redis).
4-line formula: input kahan se aaya, auth/validation kaunsa, DB ya cache ya Celery, kya return.
Related mix mat karo — cache ≠ Celery, authentication ≠ authorization, v-if ≠ v-show, Beat ≠ Worker. Follow-up ke liye ek difference ready rakho.
Example
```
POST /api/venues
PUT  /api/venues/1   {all fields}
PATCH /api/venues/1 {only name}
```
Project example: POST /api/venues create. PUT /venues/1 saari fields. PATCH sirf name.
6

Why is POST idempotent?

Times asked 2

Official solution

SimpleIdempotent = same request N baar = same effect. GET/PUT/DELETE usually; POST create duplicate ho sakta hai.
7

etc..

Times asked 2

Official solution

SimpleViva wrap-up hai. Short thanks + confirm submission ZIP latest hai.

See reviews Level3_43 MAD1 Level 3

Aug 14, 2026

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1

The same as mentioned in the response sheet.

Times asked 2

Official solution

SimpleViva wrap-up hai. Short thanks + confirm submission ZIP latest hai.
2
Infact, lesser.

Times asked 2
Official solution

SimpleServer-Sent Events: server → browser one-way stream (text/event-stream). WebSocket full duplex hai; SSE simpler notifications ke liye.
Example
```
# client
const es = new EventSource('/stream');
es.onmessage = (e) => console.log(e.data);
```
3
Run through the app

Times asked 2
Official solution

Simplevenv activate → dependencies → DB create/migrate → flask run. Browser pe localhost dikhao.
Example
```
python -m venv .venv
source .venv/bin/activate
pip install -r requirements.txt
flask run
```
4

DOM

Times asked 2

Official solution

SimpleDOM HTML tree. JS nodes change. Vue Virtual DOM ke through, direct kam.
Manipulation innerHTML vs Vue data. Remove CSS class = rules gone layout may collapse.
Pehle 1-line definition, phir related MAD2 layer (Vue SFC / Flask route / models.py / tasks.py / Redis).
4-line formula: input kahan se aaya, auth/validation kaunsa, DB ya cache ya Celery, kya return.
Related mix mat karo — cache ≠ Celery, authentication ≠ authorization, v-if ≠ v-show, Beat ≠ Worker. Follow-up ke liye ek difference ready rakho.
Project example: Inspect Elements. Vue devtools.
5
What changes to make in models to incorporate favourite songs(add a new favourites table)

Times asked 2
Official solution

Simplemodels.py = har table ki class: columns, PK/FK, relationships. Yeh Model layer hai.
Suggested flow1) Classes list karo
2) Har table ka kaam 1 line
3) Relationships (1-M / M-M)
4) Constraints (unique, nullable)
Example
```
class Lot(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    name = db.Column(db.String(80), nullable=False)
    spots = db.relationship('Spot', backref='lot', lazy=True)
```
6
Difference b/w session and cookies

Times asked 1
Official solution

SimpleMAD1 mein usually session-based auth: login pe session['user_id'], har request pe verify.
Example
```
session['user_id'] = user.id
uid = session.get('user_id')
user = User.query.get(uid)
```
Viva tipSECRET_KEY set karo warna session insecure. logout pe session.clear().

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