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Question sets

  1. 1
    Demo of App
    Times asked 4
    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. 2
    make change- show password in red next to login button on navbar
    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. 3
    Questions
    Times asked 4
    Official solution

    SimpleTheory = concepts: ORM, MVC, auth vs authz, Jinja inheritance, sessions. 1-line def + project example.

  4. 4
    - What is ORM
    Times asked 2
    Official solution

    SimpleORM = Object Relational Mapping. Tables → Python classes. Raw SQL kam likhte ho.

    Example

    class User(db.Model):
        id = db.Column(db.Integer, primary_key=True)
        email = db.Column(db.String(120), unique=True)
    
    User.query.get(5)  # SELECT ... WHERE id=5
  5. 5
    - components of celery
    Times asked 1
    Official solution

    SimpleClient (Flask .delay), Broker (Redis), Worker. Optional Beat + result backend.

    Viva line'Flask produce, Redis transport, worker consume.'

    include task modules, app context ke andar DB session. Windows pe eventlet/gevent issues — docs se command.

    Celery Python ka distributed task queue — HTTP request ko 10s email/CSV ke liye mat rokna.

    Flow: Flask .delay() → Redis broker → Worker execute. Beat alag process hai (clock): crontab padhke due time pe queue mein daalta hai. Beat khud mail nahi bhejta; Worker haath hai.

    MAD2 typical: daily reminder (Beat), monthly report (Beat), user Export CSV (button, Beat nahi). JS async/await browser event loop hai, Celery server-side process — mix mat karo.

    Demo: tin terminals — redis-server, celery worker, celery beat — plus Flask. MailHog :8025 inbox. Result backend se task SUCCESS poll optional.

    Project example: create_app ke baad celery.conf.update. tasks import taaki register hon.

    Viva tip

    Viva line'Flask task produce karta hai, Redis transport, worker consume.'

  6. 6
    - redis vs celery
    Times asked 2
    Official solution

    SimpleRedis box hai, Celery us box se kaam uthane wala worker hai — same cheez nahi.

    Redis: store (cache keys) + queue (broker lists).
    Celery: Python library jo tasks define karti hai, .delay() se queue mein daalti hai, worker execute karta hai.

    Dono localhost pe ho sakte hain. Alag Redis DB index use karo. Redis band = cache miss + Celery stuck.

    Example

    Celery: broker_url='redis://localhost:6379/0'
    Cache:  CACHE_REDIS_URL='redis://localhost:6379/1'

    Project example: export_csv.delay(user_id) Flask se. Worker Redis se task uthata hai, CSV+email. Cache alag keys venues.

    Viva tipAgar possible ho to cache db=1, broker db=0 — keys mix nahi hoti.

  7. 7
    - database structure - foreign keys, impact of deleting record which other record point to as foreign key
    Times asked 2
    Official solution

    SimpleForeign key dusri table ke PK ko point karti hai — relationship banati hai.

    Example

    lot_id = db.Column(db.Integer, db.ForeignKey('lot.id'), nullable=False)
  8. 8
    - what changes will you need to do to move to postgres from sqlite
    Times asked 2
    Official solution

    SimpleSQLite file-based DB — setup easy, MAD1 ke liye perfect. Production heavy traffic pe Postgres better.

    Example

    SQLALCHEMY_DATABASE_URI = 'sqlite:///app.db'
  1. 1
    First he asked for ID card.
    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.

  2. 2
    Full demonstration of the project.
    Times asked 3
    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. 3
    Then he randomly instructed to implement a simple feature. (like adding a button or changing the color etc..)
    Times asked 2
    Official solution

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

  4. 4
    What are ​​​Built-in Directives ?
    Times asked 1
    Official solution

    SimpleVue directive = special attr: v-if, v-for, v-model, v-bind, v-show — DOM ko declarative control.

  5. 5
    show me the code where you have implemented celery.
    Times asked 2
    Official solution

    SimpleCelery = background naukri. HTTP request ko 10 second email bhejne ke liye mat rokna.

    Distributed task queue: aap function ko abhi nahi, worker process mein later/retry/schedule pe chalaate ho.

    MAD2 typical jobs: daily reminder mail, monthly HTML report, user-triggered CSV export.

    Web request 200ms hona chahiye. 10,000 emails request thread mein = timeout. Worker alag CPU pe kaam kare.

    Redis broker chahiye. Beat alag process schedule ke liye.

    Example

    @celery.task
    def daily_reminder():
        for u in User.query.filter_by(active=True):
            send_mail(u.email, 'Book something today!')

    Project example: User Export click → 202 Accepted. Worker CSV + email. Daily 6pm Beat reminder.

    Viva tipWorker + Redis bina Beat ke user-triggered chalega. Scheduled jobs ke liye Beat bhi chahiye.

  6. 6
    show me the data models you have used. The proctor was friendly enough. He will even give his suggestions at the end :)
    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)
  1. 1
    Explain the features of the app.
    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.

  2. 2
    What you used for frontend ?
    Times asked 2
    Official solution

    SimpleMAD1 frontend usually Jinja templates + HTML/CSS/Bootstrap (+ thoda JS). MAD2 pe Vue ho to clearly bolo.

  3. 3
    Is your app responsive & how you made it responsive (I said I used bootstrap) ?
    Times asked 2
    Official solution

    SimpleBootstrap CSS framework — grid, navbar, buttons jaldi. CDN ya downloaded files.

  4. 4
    What are CSS selectors & types of CSS selectors ?
    Times asked 1
    Official solution

    Simpleelement .class #id [attr] pseudo. Specificity war. CSS selectors types.

    What are CSS selectors.

    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: .btn #app nav a:hover.

    Project example: .btn #app nav a:hover.

  5. 5
    How you implemented token based authentication ?
    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)
  6. 6
    What is authentication & authorisation ?
    Times asked 2
    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)
  1. 1
    full demo of your app
    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.

  2. 2
    certain changes in the code, like background colour, alignments
    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. 3
    git
    Times asked 1
    Official solution

    SimpleGit VCS tool. VCS concept. GitHub hosting. SCM another name.

    commit branch merge. Examiner history. Git ≠ GitHub.

    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: git log. collaborators. README.

  4. 4
    version control
    Times asked 1
    Official solution

    SimpleGit version control: commit history dikhao. VCS = Version Control System.

  5. 5
    authentication
    Times asked 3
    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)
  6. 6
    authorization
    Times asked 2
    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. 7
    libraries used in the app - here you will mostly cover:
    Times asked 2
    Official solution

    SimpleStack bolo: Python, Flask, Jinja2, SQLAlchemy, SQLite, HTML/CSS/Bootstrap, maybe Chart.js.

  8. 8
    -redis
    Times asked 1
    Official solution

    SimpleRedis fridge pe sticky note hai — poori kitchen (database) kholne ki zarurat nahi.

    Redis in-memory key-value store hai. Data RAM mein rehta hai, isliye disk wale SQLite/Postgres se kai guna tez.

    MAD2 mein Redis do kaam karta hai:
    1) Cache — same venue/show/dashboard JSON baar-baar DB se mat nikaalo.
    2) Celery message broker — Flask task queue mein daalta hai, worker uthata hai.

    Source of truth database hi hai. Redis band ho to cache miss ho jaata hai aur Celery queue ruk sakti hai. Crash pe cache gayab ho sakta hai — isliye important data sirf Redis mein mat rakho.

    Example

    import redis
    r = redis.Redis(host='localhost', port=6379, db=0)
    r.set('venues', json.dumps(data), ex=30)
    print(r.get('venues'))

    Project example: GET /api/venues pehle Redis dekho. Miss pe SQLAlchemy query, phir SET with timeout. Celery worker Redis list se daily reminder uthata hai.

    Viva tipCache ke liye db=1, broker ke liye db=0 rakhna smart hai taaki keys mix na hon. Viva mein redis-cli ping → PONG dikhana strong hai.

  9. 9
    -celery
    Times asked 1
    Official solution

    SimpleCelery = background naukri. HTTP request ko 10 second email bhejne ke liye mat rokna.

    Distributed task queue: aap function ko abhi nahi, worker process mein later/retry/schedule pe chalaate ho.

    MAD2 typical jobs: daily reminder mail, monthly HTML report, user-triggered CSV export.

    Web request 200ms hona chahiye. 10,000 emails request thread mein = timeout. Worker alag CPU pe kaam kare.

    Redis broker chahiye. Beat alag process schedule ke liye.

    Example

    @celery.task
    def daily_reminder():
        for u in User.query.filter_by(active=True):
            send_mail(u.email, 'Book something today!')

    Project example: User Export click → 202 Accepted. Worker CSV + email. Daily 6pm Beat reminder.

    Viva tipWorker + Redis bina Beat ke user-triggered chalega. Scheduled jobs ke liye Beat bhi chahiye.

  10. 10
    -flask
    Times asked 1
    Official solution

    SimpleFlask lightweight Python web framework — routes, request/response, templates. MAD1 ka backend yahi hai.

    Example

    from flask import Flask
    app = Flask(__name__)
    
    @app.route('/')
    def home():
        return 'Hello'

    Viva tipFlask micro hai: jo chahiye (DB, login, forms) khud jodte ho.

  11. 11
    -jinja2
    Times asked 2
    Official solution

    SimpleJinja2 Flask ka template engine — HTML ke andar {{ }} variables, {% %} logic.

    Example

    {% for lot in lots %}
      <li>{{ lot.name }} — {{ lot.spots }}</li>
    {% else %}
      <p>No lots</p>
    {% endfor %}
  12. 12
    -api
    Times asked 1
    Official solution

    SimpleAPI = interface jisse systems baat karein. Web API usually JSON return karti hai.

    Example

    @app.route('/api/lots')
    def api_lots():
        return jsonify([{'id': l.id, 'name': l.name} for l in Lot.query.all()])
  13. 13
    -sqlalchemy
    Times asked 2
    Official solution

    SimpleSQLAlchemy MAD1 ka common ORM. Flask-SQLAlchemy wrapper se db.Model, db.session.

    Example

    user = User(email='a@b.com')
    db.session.add(user)
    db.session.commit()
    users = User.query.filter_by(role='admin').all()
  1. 1
    Demonstration of all the functionalities of project
    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.

  2. 2
    which tokenization are you using
    Times asked 2
    Official solution

    SimpleJWT teen tukde ki signed chitthi: header.payload.signature. Padhi ja sakti hai, badli nahi ja sakti.

    Encoded (Base64) + signed, encrypted nahi (JWE alag). Payload mein password mat daalo — koi jwt.io pe dekh lega.

    Login pe server secret se HMAC (HS256). Har API Authorization: Bearer <token>.
    Expiry exp. Change payload → signature fail → 401.

    Session MAD1 server yaad rakhta. JWT MAD2 client rakhta, server stateless-ish.

    Example

    eyJhbGciOiJIUzI1NiJ9.{"sub":1,"role":"admin"}.signature
    # Authorization: Bearer <token>

    Project example: POST /login → token LS. fetch interceptor header. @jwt_required APIs.

    Viva tipAlgo HS256. Secret env var. jwt.io pe payload dikhao, secret public site pe mat paste.

  3. 3
    tested the page which can only be accessed by admin by copying the URL and opening it in the incognito mode
    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);
  4. 4
    what is virtualDOM
    Times asked 2
    Official solution

    SimpleVirtual DOM = UI ka lightweight JS copy. Change pe diff → minimal real DOM update. Vue/React isliye tez re-render.

  5. 5
    how does a parent communicates with a child
    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. 6
    how do we pass props
    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.

  7. 7
    difference between primary key and unique key
    Times asked 1
    Official solution

    SimplePrimary Key table ki main identity hai (ek hi), Unique Key extra unique column ho sakta hai (kai).

    PK: NOT NULL + UNIQUE, sirf ek clustered identity. Example: id
    Unique: duplicate nahi, lekin NULL allow ho sakta hai. Example: email, username

    UNIQUE + NOT NULL + AUTO_INCREMENT PK jaisa behave karta hai, lekin table ki official PK nahi. Relationships/FK generally PK ko refer karti hain.
    Isliye alag Primary Key rakhna better hai.

  8. 8
    give me an example where you will use v-if vs v-show
    Times asked 2
    Official solution

    Simplev-if ghar se nikaal deta hai (DOM se). v-show sirf light band karta hai (display:none).

    v-if false → element exist hi nahi — costly create/destroy, lekin secret HTML DOM mein nahi.
    v-show → hamesha DOM, CSS hide, toggle tez.

    Rare / permission UI: v-if (admin panel). Dropdown bar-bar: v-show.

    : shorthand v-bind ka, v-if ka nahi.

    Example

    <div v-if="isAdmin">Admin panel</div>
    <div v-show="open">Dropdown</div>

    Project example: Admin links v-if="role==='admin'". FAQ accordion v-show="open".

    Viva tipSecurity ke liye sirf v-if kaafi nahi — API 403 bhi chahiye.

  9. 9
    asked me to change the colour of navbar
    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.

  10. 10
    tell me about message broker
    Times asked 2
    Official solution

    SimpleRedis. Alternative RabbitMQ. Course Redis because cache bhi.

    Between Flask client and Celery worker.

    Celery Python ka distributed task queue — HTTP request ko 10s email/CSV ke liye mat rokna.

    Flow: Flask .delay() → Redis broker → Worker execute. Beat alag process hai (clock): crontab padhke due time pe queue mein daalta hai. Beat khud mail nahi bhejta; Worker haath hai.

    MAD2 typical: daily reminder (Beat), monthly report (Beat), user Export CSV (button, Beat nahi). JS async/await browser event loop hai, Celery server-side process — mix mat karo.

    Demo: tin terminals — redis-server, celery worker, celery beat — plus Flask. MailHog :8025 inbox. Result backend se task SUCCESS poll optional.

    Project example: broker_url redis://localhost:6379/0

  11. 11
    async functions in JS
    Times asked 2
    Official solution

    Simpleasync function promise return karti hai. await us promise ka result wait karta hai — callback hell kam.

    Example

    async function loadLots() {
      const res = await fetch('/api/lots');
      const data = await res.json();
      return data;
    }
  12. 12
    ...it went smooth he was very calm and understanding.
    Times asked 2
    Official solution

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

  1. 1
    Examiner
    Times asked 2
    Official solution

    SimpleTheory = concepts: ORM, MVC, auth vs authz, Jinja inheritance, sessions. 1-line def + project example.

  2. 2
    Level3_26_MAD2_Viva
    Times asked 2
    Official solution

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

  3. 3
    Questions
    Times asked 4
    Official solution

    SimpleTheory = concepts: ORM, MVC, auth vs authz, Jinja inheritance, sessions. 1-line def + project example.

  4. 4
    Full demo
    Times asked 3
    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. 5
    Checked even validations for login/register - Password validation for login was there but not for register. He asked me to fix it. I did.
    Times asked 2
    Official solution

    SimpleValidation = input rules: required, email format, length, unique. Frontend UX, backend security — dono.

    Example

    if not email or '@' not in email:
        flash('Invalid email')
        return redirect(request.url)
    if User.query.filter_by(email=email).first():
        flash('Email taken')
  6. 6
    Checked the database, asked why category_request table was made.
    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.

  7. 7
    Asked to check if user can access admin page (by changing the url) - on front end user could, but none of the buttons worked when authenticated. He asked me if I can change code to make sure user gets redirected to login page if admin page url is pasted. I couldn't do that.
    Times asked 2
    Official solution

    Simpleredirect dusre URL pe bhejta hai. flash one-time message session mein rakh ke next page pe dikhata hai.

    Example

    flash('Login successful', 'success')
    return redirect(url_for('user.dashboard'))
  8. 8
    Asked about security - what I used and all the details. I answered those.
    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.

  9. 9
    Asked if I used VueX store, I did and I explained what I have implemented.
    Times asked 2
    Official solution

    SimpleVue = UI ka smart assistant. Data badlo, screen khud update. MAD1 Jinja har click pe naya HTML.

    Progressive frontend framework. Components, reactivity, directives.

    MAD2 SPA: ek index.html, Vue Router pages, Flask sirf JSON.

    Fayde: easy, SFC, docs. Vs React: templates HTML-like, course sikhata hai. Vs plain JS: baar-baar DOM mat chhedo.

    Example

    <!-- HelloWorld.vue -->
    <template>
      <h1>{{ msg }}</h1>
    </template>
    <script>
    export default { data() { return { msg: 'Hello' } } }
    </script>

    Project example: Navbar.vue + views (Login, Dashboard). data() / setup() reactive. fetch APIs.

    Viva tipFayde: easy, SFC, reactivity. Vs React: chhota learning curve. Vs plain JS: UI state auto-update.

  10. 10
    V-if, v-show differences
    Times asked 2
    Official solution

    Simplev-if ghar se nikaal deta hai (DOM se). v-show sirf light band karta hai (display:none).

    v-if false → element exist hi nahi — costly create/destroy, lekin secret HTML DOM mein nahi.
    v-show → hamesha DOM, CSS hide, toggle tez.

    Rare / permission UI: v-if (admin panel). Dropdown bar-bar: v-show.

    : shorthand v-bind ka, v-if ka nahi.

    Example

    <div v-if="isAdmin">Admin panel</div>
    <div v-show="open">Dropdown</div>

    Project example: Admin links v-if="role==='admin'". FAQ accordion v-show="open".

    Viva tipSecurity ke liye sirf v-if kaafi nahi — API 403 bhi chahiye.

  11. 11
    Props, parent to child, child to parent communication
    Times asked 2
    Official solution

    SimpleProps parent ki thali child ko dena. Child thali tod ke parent ki thali na badle — emit bolo.

    Declare props, parent :venue="v". One-way. Mutate mat. Types/required Vue 3.

    List parent, card child — classic viva.

    Component = reusable UI block (Navbar, Card). Props parent→child data, emit child→parent event. Slots parent HTML inner content.

    computed cache + reactive derive (filtered list). watch side-effect (query change pe API). methods events. ref() primitive, reactive() object. Vuex/Pinia global store; localStorage persist, store nahi.

    SFC: template + script + style ek .vue file. Parent-child exam favourite: list parent, row child :item + @delete.

    Example

    <VenueCard :venue="v" @select="onSelect" />
    props: ['venue']
    this.$emit('select', this.venue.id)

    Project example: VenueCard :venue. Child $emit('select', id).

  12. 12
    Vue vs react
    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.

  13. 13
    Flask vs other frame works
    Times asked 2
    Official solution

    SimpleFlask lightweight Python web framework — routes, request/response, templates. MAD1 ka backend yahi hai.

    Example

    from flask import Flask
    app = Flask(__name__)
    
    @app.route('/')
    def home():
        return 'Hello'

    Viva tipFlask micro hai: jo chahiye (DB, login, forms) khud jodte ho.

  14. 14
    Asked if my app was scalable to the size of big basket. I said no. He asked for all the reasons right from backend, frameworks, db, frontend etc. Answered as much as I could.
    Times asked 2
    Official solution

    SimpleStack bolo: Python, Flask, Jinja2, SQLAlchemy, SQLite, HTML/CSS/Bootstrap, maybe Chart.js.

  15. 15
    Asked if flask is ok if you want to scale. I said yes.
    Times asked 2
    Official solution

    SimpleFlask lightweight Python web framework — routes, request/response, templates. MAD1 ka backend yahi hai.

    Example

    from flask import Flask
    app = Flask(__name__)
    
    @app.route('/')
    def home():
        return 'Hello'

    Viva tipFlask micro hai: jo chahiye (DB, login, forms) khud jodte ho.

  16. 16
    SQL injection
    Times asked 1
    Official solution

    SimpleUser input concat query. ORM bound params bachata. text()+user mat.

    SQLAlchemy injection still if format SQL.

    Browser + API ke beech extra darwaze: CORS origin allow, HTTPS encrypt transit, CSRF cookie-auto-send attack, XSS HTML inject, SQL injection raw query.

    MAD2 SPA: Vue :8080 Flask :5000 → Flask-CORS. JWT localStorage XSS se chori ho sakta — v-html user input pe avoid. Password Network tab localhost pe dikhega; prod HTTPS, response mein password echo nahi.

    401 unauthenticated, 403 unauthorized, 400 validation. Hash one-way — SHA decrypt nahi hota. Secret key .env, GitHub pe nahi.

    Example

    # bad: f"SELECT * FROM user WHERE name='{name}'"
    User.query.filter_by(name=name)  # good

    Project example: filter_by(name=name) good.

  17. 17
    Python 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
  18. 18
    And some more
    Times asked 2
    Official solution

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

  1. 1
    What are Vue components and Vue directives?
    Times asked 1
    Official solution

    SimpleComponent Lego block: UI + data. Pages routes, components unke andar.

    Bahut files = maintainable Navbar/Footer. Not a bug.

    Component = reusable UI block (Navbar, Card). Props parent→child data, emit child→parent event. Slots parent HTML inner content.

    computed cache + reactive derive (filtered list). watch side-effect (query change pe API). methods events. ref() primitive, reactive() object. Vuex/Pinia global store; localStorage persist, store nahi.

    SFC: template + script + style ek .vue file. Parent-child exam favourite: list parent, row child :item + @delete.

    Example

    app.component('Hello', { template: '<p>Hi {{ name }}</p>', props: ['name'] })

    Project example: src/components vs views. router uses views.

    Viva tipBahut Vue files isliye: har page/feature alag — maintainable. Navbar layout har route pe.

  2. 2
    What is ORM?
    Times asked 49
    Official solution

    SimpleORM = Object Relational Mapping. Database tables ko Python classes/objects se map karta hai, raw SQL kam likhni padti hai.

    Bina ORM: cursor.execute('SELECT * FROM user WHERE id=?', [5])
    ORM se: User.query.get(5) ya db.session.get(User, 5)

    Example model

    class User(db.Model):
        id = db.Column(db.Integer, primary_key=True)
        email = db.Column(db.String(120), unique=True)

    FaydePython mein soch sakte ho, SQL injection se protection (parameterized), relationships easy, DB switch thoda aasan.

    Nuksaancomplex queries slow/abstract, seekhne ki layer extra, kabhi raw SQL phir bhi chahiye.

    MAD1: SQLAlchemy (Flask-SQLAlchemy). Tables db.create_all() ya migrations se banti hain.

  3. 3
    what is Webhook and API?
    Times asked 1
    Official solution

    SimpleWebhook = woh tumhe call karta hai. API = tum unhe call karte ho.

    Payment success pe Stripe tumhare /webhooks/payment pe POST. Tum poll nahi karte.

    API pull, webhook push. WebSocket dono taraf live connection. SSE server→client stream.

    MAD2 mostly REST APIs. Webhook theory + example kaafi. Verify signature production mein.

    Example

    @app.route('/webhooks/payment', methods=['POST'])
    def hook():
        event = request.json
        ...

    Project example: Agar implement nahi: 'course REST. Webhook design: POST /webhooks/booking-paid'.

    Viva tipAPI pull, webhook push. WebSocket dono taraf live. SSE server → client stream.

  4. 4
    what is SQL alchemy?
    Times asked 2
    Official solution

    SimpleSQLAlchemy MAD1 ka common ORM. Flask-SQLAlchemy wrapper se db.Model, db.session.

    Example

    user = User(email='a@b.com')
    db.session.add(user)
    db.session.commit()
    users = User.query.filter_by(role='admin').all()
  5. 5
    How long did it take to create this app?
    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. 6
    He told me to limit the price of the products to prevent them from going beyond a certain range.
    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.

  1. 1
    1.Vast demo of application
    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.

  2. 2
    2.Ask about how your access tokens are working?
    Times asked 2
    Official solution

    SimpleJWT teen tukde ki signed chitthi: header.payload.signature. Padhi ja sakti hai, badli nahi ja sakti.

    Encoded (Base64) + signed, encrypted nahi (JWE alag). Payload mein password mat daalo — koi jwt.io pe dekh lega.

    Login pe server secret se HMAC (HS256). Har API Authorization: Bearer <token>.
    Expiry exp. Change payload → signature fail → 401.

    Session MAD1 server yaad rakhta. JWT MAD2 client rakhta, server stateless-ish.

    Example

    eyJhbGciOiJIUzI1NiJ9.{"sub":1,"role":"admin"}.signature
    # Authorization: Bearer <token>

    Project example: POST /login → token LS. fetch interceptor header. @jwt_required APIs.

    Viva tipAlgo HS256. Secret env var. jwt.io pe payload dikhao, secret public site pe mat paste.

  3. 3
    3.Redis
    Times asked 2
    Official solution

    SimpleRedis fridge pe sticky note hai — poori kitchen (database) kholne ki zarurat nahi.

    Redis in-memory key-value store hai. Data RAM mein rehta hai, isliye disk wale SQLite/Postgres se kai guna tez.

    MAD2 mein Redis do kaam karta hai:
    1) Cache — same venue/show/dashboard JSON baar-baar DB se mat nikaalo.
    2) Celery message broker — Flask task queue mein daalta hai, worker uthata hai.

    Source of truth database hi hai. Redis band ho to cache miss ho jaata hai aur Celery queue ruk sakti hai. Crash pe cache gayab ho sakta hai — isliye important data sirf Redis mein mat rakho.

    Example

    import redis
    r = redis.Redis(host='localhost', port=6379, db=0)
    r.set('venues', json.dumps(data), ex=30)
    print(r.get('venues'))

    Project example: GET /api/venues pehle Redis dekho. Miss pe SQLAlchemy query, phir SET with timeout. Celery worker Redis list se daily reminder uthata hai.

    Viva tipCache ke liye db=1, broker ke liye db=0 rakhna smart hai taaki keys mix na hon. Viva mein redis-cli ping → PONG dikhana strong hai.

  4. 4
    4.Vue-Props
    Times asked 2
    Official solution

    SimpleVue = UI ka smart assistant. Data badlo, screen khud update. MAD1 Jinja har click pe naya HTML.

    Progressive frontend framework. Components, reactivity, directives.

    MAD2 SPA: ek index.html, Vue Router pages, Flask sirf JSON.

    Fayde: easy, SFC, docs. Vs React: templates HTML-like, course sikhata hai. Vs plain JS: baar-baar DOM mat chhedo.

    Example

    <!-- HelloWorld.vue -->
    <template>
      <h1>{{ msg }}</h1>
    </template>
    <script>
    export default { data() { return { msg: 'Hello' } } }
    </script>

    Project example: Navbar.vue + views (Login, Dashboard). data() / setup() reactive. fetch APIs.

    Viva tipFayde: easy, SFC, reactivity. Vs React: chhota learning curve. Vs plain JS: UI state auto-update.

  5. 5
    5.which function will you use to pass data child to parent?
    Times asked 2
    Official solution

    SimpleChild → parent: $emit / defineEmits. Parent @event sunta hai.

    Example

    // child
    this.\$emit('saved', payload)
    // parent
    <Child @saved="onSaved" />
  6. 6
    6.Vuex and vue-routers
    Times asked 2
    Official solution

    SimpleVue = UI ka smart assistant. Data badlo, screen khud update. MAD1 Jinja har click pe naya HTML.

    Progressive frontend framework. Components, reactivity, directives.

    MAD2 SPA: ek index.html, Vue Router pages, Flask sirf JSON.

    Fayde: easy, SFC, docs. Vs React: templates HTML-like, course sikhata hai. Vs plain JS: baar-baar DOM mat chhedo.

    Example

    <!-- HelloWorld.vue -->
    <template>
      <h1>{{ msg }}</h1>
    </template>
    <script>
    export default { data() { return { msg: 'Hello' } } }
    </script>

    Project example: Navbar.vue + views (Login, Dashboard). data() / setup() reactive. fetch APIs.

    Viva tipFayde: easy, SFC, reactivity. Vs React: chhota learning curve. Vs plain JS: UI state auto-update.

  7. 7
    7.what is vuejs and their benifits?
    Times asked 1
    Official solution

    SimpleVue = UI ka smart assistant. Data badlo, screen khud update. MAD1 Jinja har click pe naya HTML.

    Progressive frontend framework. Components, reactivity, directives.

    MAD2 SPA: ek index.html, Vue Router pages, Flask sirf JSON.

    Fayde: easy, SFC, docs. Vs React: templates HTML-like, course sikhata hai. Vs plain JS: baar-baar DOM mat chhedo.

    Example

    <!-- HelloWorld.vue -->
    <template>
      <h1>{{ msg }}</h1>
    </template>
    <script>
    export default { data() { return { msg: 'Hello' } } }
    </script>

    Project example: Navbar.vue + views (Login, Dashboard). data() / setup() reactive. fetch APIs.

    Viva tipFayde: easy, SFC, reactivity. Vs React: chhota learning curve. Vs plain JS: UI state auto-update.

  8. 8
    8.full knowledge of database
    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.

  9. 9
    9.Primary ,unique and foreign keys
    Times asked 2
    Official solution

    SimpleForeign key dusri table ke PK ko point karti hai — relationship banati hai.

    Example

    lot_id = db.Column(db.Integer, db.ForeignKey('lot.id'), nullable=False)
  10. 10
    10.Authorization and Authentication
    Times asked 2
    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)
  11. 11
    11.Some questions from javascript itself like event-loop ,promises
    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.

  12. 12
    12.v-if and v-show
    Times asked 2
    Official solution

    Simplev-if ghar se nikaal deta hai (DOM se). v-show sirf light band karta hai (display:none).

    v-if false → element exist hi nahi — costly create/destroy, lekin secret HTML DOM mein nahi.
    v-show → hamesha DOM, CSS hide, toggle tez.

    Rare / permission UI: v-if (admin panel). Dropdown bar-bar: v-show.

    : shorthand v-bind ka, v-if ka nahi.

    Example

    <div v-if="isAdmin">Admin panel</div>
    <div v-show="open">Dropdown</div>

    Project example: Admin links v-if="role==='admin'". FAQ accordion v-show="open".

    Viva tipSecurity ke liye sirf v-if kaafi nahi — API 403 bhi chahiye.

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