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Question sets

  1. 1
    Showcase 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
    Explain the components in your 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.

  1. 1
    Very good proctor
    Times asked 2
    Official solution

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

  2. 2
    Asked Demo of the app
    Times asked 3
    Official solution

    SimpleDemo script pehle se practice karo, 5-7 minute, saari roles.

    Suggested flow

    1) Register/login user 2) Admin login — CRUD 3) Approval/blacklist 4) Booking/apply 5) Search 6) Validation edge (slots 0, duplicate) 7) Logout
    Bolte-bolte dikhao: 'Yahan overbooking rokta hoon'. Code tab kholna jab poochhein.
    Crash ho to debug calmly: terminal error, typo, DB path.
    Mandatory features skip mat karna — examiner list tick karta hai.

  3. 3
    Show models and explain
    Times asked 2
    Official solution

    Simplemodels.py har table ki class hai — columns, PK/FK, relationships. Yeh Model layer hai.

    Viva mein file khol ke bolo:
    1) Kaunsi classes/tables hain (User, Role-specific, Booking...)
    2) Har table ka kaam 1 line
    3) Relationships: 1-1 / 1-M / M-M, backref, cascade, lazy
    4) Constraints: unique email, nullable, default status

    Example skeleton

    class User(db.Model):
        id = db.Column(db.Integer, primary_key=True)
        email = db.Column(db.String(120), unique=True, nullable=False)
        role = db.Column(db.String(20), default='user')
        bookings = db.relationship('Booking', backref='user', cascade='all, delete-orphan')

    ER diagram: rectangles entities, lines relationships, PK/FK mark. Schema = yahi structure.
    Tables create: db.create_all() ya migrations. SQLite file SQL viewer se dikha sakte ho.

  4. 4
    why you are using fs_uniquifier
    Times asked 2
    Official solution

    SimpleUserMixin Flask-Login ko batata hai user object kaise treat karna hai (is_authenticated, get_id).

    class User(db.Model, UserMixin):
        id = db.Column(db.Integer, primary_key=True)

    current_user proxy logged-in user. Initialize: login_user(user) / user_loader callback.
    Flask-WTF: Python classes se forms, CSRF, validators. RegisterForm forms.py mein.
    fs_uniquifier Flask-Security mein token/session identity — email change pe sessions invalidate.
    enctype='multipart/form-data' file upload pe zaroori. request.files.get('resume').

  5. 5
    How RBAC implemented
    Times asked 2
    Official solution

    SimpleRBAC = Role-Based Access Control — permission role se (admin/staff/user), har user pe alag nahi.

    user.role = 'admin'
    if current_user.role != 'admin': abort(403)

    Same login page, role ke hisaab dashboard. Multiple roles: roles table Many-to-Many, ya comma field (behtar normalized table).
    Unapproved staff: is_approved flag, login pe check.
    Flask-Security/UserMixin is_authenticated, is_active, get_id dete hain.

  6. 6
    caching
    Times asked 2
    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. 7
    Explain props in vue
    Times asked 3
    Official solution

    SimpleVue.js frontend framework — reactive UI components. MAD2 mein common, MAD1 optional.

    Component: reusable UI (Navbar.vue) + data + template.
    Props: parent → child data. Child → parent: $emit('update', val).
    Slots: parent child ke andar extra HTML daal sakta hai.
    Lifecycle: created (data setup), mounted (DOM ready — API call), updated, unmounted.
    v-model two-way bind. Vue Router SPA routes (routes.js). Vuex/Pinia global state; mutations sync change, actions async.
    Standalone component: khud ke saath compile, parent register kam.

  8. 8
    Different Lifecycle hooks in vue
    Times asked 2
    Official solution

    SimpleVue.js frontend framework — reactive UI components. MAD2 mein common, MAD1 optional.

    Component: reusable UI (Navbar.vue) + data + template.
    Props: parent → child data. Child → parent: $emit('update', val).
    Slots: parent child ke andar extra HTML daal sakta hai.
    Lifecycle: created (data setup), mounted (DOM ready — API call), updated, unmounted.
    v-model two-way bind. Vue Router SPA routes (routes.js). Vuex/Pinia global state; mutations sync change, actions async.
    Standalone component: khud ke saath compile, parent register kam.

  9. 9
    show job Scheduling report
    Times asked 2
    Official solution

    SimpleCelery background tasks (email, CSV, reports) async chalaata hai. Redis broker/queue + cache.

    User 'Export' click → Celery task queue → Redis message → worker CSV banaata hai → user baad mein download.
    Saath isliye: Celery ko broker chahiye, Redis tez in-memory. MAD2 topic zyada, MAD1 mein optional.
    Priority: task queues/routing. Caching: Redis mein key-value, DB hits kam.
    Pub/Sub: publisher channel pe message, subscribers sunte hain — Redis yeh bhi karta hai.

  10. 10
    no code changes were asked
    Times asked 3
    Official solution

    Yeh MAD-1 viva question tumhare project ke context se linked hai. Short answer is structure se do:

    Pehle 1 line definition/purpose, phir tumhare project ka example, phir chhota code/flow.

    Typical Flask flowBrowser request → @app.route controller → SQLAlchemy model/DB → Jinja template response.

    Auth: session['user_id'] + role check. CRUD: add/commit, query.all, field update, delete.
    Live change maange to: related model → route → template, phir browser refresh karke dikhao.

    Example (generic create):
    obj = Model(name=request.form.get('name'))

    db.session.add(obj); db.session.commit()
    return redirect(url_for('list_view'))
  1. 1
    Explain you db 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)
  2. 2
    Explain all APIs (i explained my complete app.py file) after 20 mins of explanation he asked this question- What is scaling and how you would scale this project if you had more than 10000 users?
    Times asked 1
    Official solution

    SimpleCode explain formula: input kya aaya → auth/validation → DB change → response/UI.

    Viva tipFunction signature + 3-4 important lines + edge case.

Advice: know your code well (specifically the models and endpoints)
  1. 1
    Viva Lvl2 proctor 2_144 5-6pm
    Times asked 2
    Official solution

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

  2. 2
    Asked for Id
    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. 3
    Download submission from portal
    Times asked 3
    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. 4
    explain me the directory structure of ur 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.

  5. 5
    which version of vue r u using 2 or 3?
    Times asked 1
    Official solution

    Simple2 or 3 from package.json + 1 difference Composition/filters.

    Which version are you using.

    SPA = ek HTML, Vue Router se views, full reload nahi. MPA = MAD1 Jinja har URL naya HTML.

    Vue Router: routes array, router-view, router-link, meta.auth + beforeEach guard. Dynamic /venues/:id$route.params.id.

    Vite/CLI SFC + npm build dist/. CDN script tag, no SFC. Jo tumne use kiya wahi justify. Flask send_from_directory('dist') production pattern.

    Project example: package.json vue field.

    Project example: package.json vue field.

  6. 6
    Difference between vue cli and cdn?
    Times asked 1
    Official solution

    SimpleCDN = Vue script tag se, jaise pen drive. CLI/Vite = poori factory (SFC, npm, bundle).

    CDN: no build, chhote apps, exam PC pe Node nahi to bhi chal. Weak: no .vue compile, 3rd-party cache, scale/team.

    CLI/Vite: Single File Components, env, code-split, production dist/. Scalable.

    Examiner 'which + why' — jo use kiya wahi justify, doosra naam rato mat.

    Example

    <!-- CDN -->
    <script src="https://unpkg.com/vue@3/dist/vue.global.js"></script>
    
    # Vite
    npm run dev
    npm run build

    Project example: CDN: index.html unpkg vue. CLI: package.json, npm run serve / vite.

    Viva tipCDN scalable large teams ke liye weak (no SFC compile, caching 3rd party). Examiner 'which + why' poochta hai — jo use kiya wahi justify karo.

  7. 7
    Why u have used cdn? Show me where u have used it (in index.html)
    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.

  8. 8
    How many vue files u have in total?
    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.

  9. 9
    Open and explain any 1 of them
    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.

  10. 10
    explain models.py
    Times asked 4
    Official solution

    Simplemodels.py har table ki class hai — columns, PK/FK, relationships. Yeh Model layer hai.

    Viva mein file khol ke bolo:
    1) Kaunsi classes/tables hain (User, Role-specific, Booking...)
    2) Har table ka kaam 1 line
    3) Relationships: 1-1 / 1-M / M-M, backref, cascade, lazy
    4) Constraints: unique email, nullable, default status

    Example skeleton

    class User(db.Model):
        id = db.Column(db.Integer, primary_key=True)
        email = db.Column(db.String(120), unique=True, nullable=False)
        role = db.Column(db.String(20), default='user')
        bookings = db.relationship('Booking', backref='user', cascade='all, delete-orphan')

    ER diagram: rectangles entities, lines relationships, PK/FK mark. Schema = yahi structure.
    Tables create: db.create_all() ya migrations. SQLite file SQL viewer se dikha sakte ho.

  11. 11
    difference between back_populates and backref
    Times asked 1
    Official solution

    Simplebackref reverse attribute auto banata hai. back_populates dono sides explicitly naam dete ho — clearer.

    Example

    # backref
    spots = db.relationship('Spot', backref='lot')
    # spot.lot available
    
    # back_populates
    spots = db.relationship('Spot', back_populates='lot')
    # Spot.lot = db.relationship('Lot', back_populates='spots')
  12. 12
    explain RBAC in ur app
    Times asked 2
    Official solution

    SimpleRBAC = Role Based Access Control. Roles (admin/user) se permissions milti hain, har user pe alag list nahi.

    Example

    if current_user.role != 'admin':
        flash('Not allowed')
        return redirect(url_for('user.home'))
  13. 13
    how role_required decorator is working
    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
  14. 14
    what is cache?
    Times asked 1
    Official solution

    SimpleCache = pehli baar hisaab karke copy rakh lo, doosri baar copy dikha do.

    Baar-baar same expensive kaam (DB query, counting bookings) mat karo. Result Redis jaise store mein timeout ke saath rakh do.

    Cache hit: key mil gayi, DB skip. Cache miss: DB se lao, SET karo, return karo.

    Tradeoff: speed vs stale data. Admin naya venue add kare aur cache 50s ka ho to user purani list dekh sakta hai — isliye write pe invalidation zaroori hai.

    Browser cache, Flask-Caching, Redis alag layers hain. MAD2 examiner Redis + @cache.cached code dekhta hai.

    Example

    @cache.cached(timeout=50, query_string=True)
    @app.route('/api/shows')
    def shows():
        return jsonify([s.serialize() for s in Show.query.all()])

    Project example: Admin dashboard counts / venues list cache. Create/update/delete ke baad cache.delete('venues').

    Viva tipprint('DB queried') function ke andar laga ke miss/hit demo karo — hit pe print nahi chalega.

  15. 15
    schedule the time in celery to send monthly report and daily reminder at 5:20pm
    Times asked 2
    Official solution

    SimpleLive jobs: Redis, worker, beat, crontab abhi, logs + email/CSV.

    Scheduled vs user-triggered dono dikhao. Missing feature honestly.

    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) redis
    2) worker
    3) beat
    4) crontab now
    5) logs + MailHog

    Example

    CELERY_BEAT_SCHEDULE = {
      'daily-reminder': {
        'task': 'jobs.daily_reminder',
        'schedule': crontab(hour=18, minute=0),
      },
    }

    Project example: Change schedule current time. MailHog. Export button 202.

  16. 16
    what is v-if and v-show
    Times asked 1
    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.

  17. 17
    what will happen if backend sends a 400 http code response, how ur frontend will catch that 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.

  18. 18
    give short 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.

  19. 19
    how many types of storage are there in browser?
    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.

  20. 20
    where redis store its cache?
    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.

  21. 21
    what u know about vuex store?
    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.

  22. 22
    what are state, mutation and actions?
    Times asked 2
    Official solution

    SimpleMutations sync diary entry. Actions async kaam phir diary.

    Direct state mutate action se Vuex 4 discouraged. Devtools time-travel mutations.

    Purpose of Actions: API, phir commit. Purpose of Mutations: state change one place.

    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: action fetchVenues → commit setVenues. Mutation sirf array replace.

  23. 23
    what is the use of actions?
    Times asked 1
    Official solution

    SimpleState management (Vuex/Pinia): shared app state. Advantage: props drilling kam, auth/cart central.

  24. 24
    how r u rendering charts in ur app? ( i was using chart js)
    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.

  25. 25
    change the bars in chartjs to take only 2 colors
    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.

  26. 26
    I find proctor neither rude nor friendly
    Times asked 2
    Official solution

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

  27. 27
    he ask ques mainly from project 80% from proj and 20% from theory (atleast in my case)
    Times asked 2
    Official solution

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

  28. 28
    viva took 1hr
    Times asked 2
    Official solution

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

  29. 29
    overall good experience
    Times asked 2
    Official solution

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

Advice: just be thorough with ur project
  1. 1
    * Show the components in your code
    Times asked 2
    Official solution

    SimpleCode dikhao to pehle related file: models → route → template. Flow explain karte hue lines padho.

  2. 2
    * Why have you used session storage instead of local storage
    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().

  3. 3
    * Vue lifecycle and hooks
    Times asked 2
    Official solution

    SimpleLifecycle = component ki zindagi ke stages. API call tab jab DOM ready ho — mounted.

    created: instance bani, this data, DOM nahi. mounted/onMounted: page pe aa gaya — fetch, Chart.js, setInterval.
    updated: data change ke baad. unmounted: cleanup (clearInterval) warna memory leak.

    Dashboards onMounted isliye: canvas/API tab valid. created mein $el nahi.

    Composition: onMounted(() => {}) setup ke andar.

    Example

    export default {
      async mounted() {
        const r = await fetch('/api/venues')
        this.venues = await r.json()
      }
    }

    Project example: Venues.vue mounted fetch list. Clock component unmounted pe interval clear.

    Viva tipcreated: data setup, DOM nahi. mounted/onMounted: $el mil gaya — fetch yahi. Dashboards isliye onMounted use karti hain.

  4. 4
    * Have you used state management? What is the advantage?
    Times asked 2
    Official solution

    SimpleState management (Vuex/Pinia): shared app state. Advantage: props drilling kam, auth/cart central.

  5. 5
    * In models I had used tablename, so what would happen if I didn't
    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. 6
    * What is RoleMixin
    Times asked 2
    Official solution

    SimpleUserMixin RoleMixin Flask-Security interfaces: is_authenticated, roles relation.

    Methods milte. Models inherit.

    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: class User(db.Model, UserMixin).

  7. 7
    * What is relationship
    Times asked 1
    Official solution

    Simpledb.relationship se object graph: lot.spots, booking.user. backref reverse side auto deta hai.

    Example

    spots = db.relationship('Spot', backref='lot', cascade='all, delete-orphan')
  8. 8
    * What is backref? Difference between backref and backpopulate?
    Times asked 1
    Official solution

    Simplebackref reverse attribute auto banata hai. back_populates dono sides explicitly naam dete ho — clearer.

    Example

    # backref
    spots = db.relationship('Spot', backref='lot')
    # spot.lot available
    
    # back_populates
    spots = db.relationship('Spot', back_populates='lot')
    # Spot.lot = db.relationship('Lot', back_populates='spots')
  9. 9
    * What is cascade all etc
    Times asked 1
    Official solution

    SimpleCascade parent delete pe children pe kya ho: delete-orphan related rows hata deta hai.

    Example

    db.relationship('Spot', cascade='all, delete-orphan')

    Viva tipParking lot delete → uske spots/bookings policy clear bolo.

  10. 10
    * What all changes will be required if we want to migrate to some other database
    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'
  11. 11
    * Some demonstration
    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.

  12. 12
    * Authorization vs 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)
  13. 13
    * Status code for unauthorised access
    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.

  14. 14
    * What are webhooks?
    Times asked 2
    Official solution

    SimpleWebSocket do-tarfa live connection, Webhook 'kisi event pe URL hit karo'.

    WebSocket: chat, live scores. Connection open rehti hai.
    Webhook: payment success pe Stripe tumhari /webhook URL POST karta hai. Connection nahi, ek HTTP call.
    MAD1 mein usually nahi hote; REST request-response hota hai.

  15. 15
    * Are webhook requests client side or server side?
    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.

  16. 16
    * What is ilike?
    Times asked 2
    Official solution

    SimpleLIKE case-sensitive Postgres. ILIKE insensitive. SQLite LIKE often insensitive.

    Search use ilike.

    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: Venue.name.ilike(f'%{q}%').

    Project example: Venue.name.ilike(f'%{q}%').

  17. 17
    * If you have set a unique constraint on a column and you try to insert a duplicate entry, what error will you get?
    Times asked 2
    Official solution

    SimpleInt column mein string daalne pe SQLAlchemy/DB type error ya Integrity/StatementError. Empty table pe bhi same validation fail — row count matter nahi.

    Example

    # SQLite may coerce sometimes; Postgres: invalid input syntax for integer
    Spot(status='free', lot_id='abc')  # lot_id int → error
  18. 18
    * Cache vs memoise
    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.

  19. 19
    * Code change: Asked to show number of days remaining before the book access will be revoked
    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.

Advice: If you don't know some answer, hint it like giving short reply. He will understand and won't ask that in detail.
  1. 1
    What is caching ?
    Times asked 1
    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.

  2. 2
    Indexing in database ?
    Times asked 1
    Official solution

    SimpleIndex = column pe shortcut book — WHERE/JOIN tez. PK auto-indexed. Email/unique filters pe index socho.

    Example

    email = db.Column(db.String(120), unique=True, index=True)
  3. 3
    Jwt token , validity and its expiry ?
    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.

  4. 4
    Celery
    Times asked 9
    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.

  5. 5
    Redis
    Times asked 6
    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.

  6. 6
    Is you application scalable ? If yes , How ?
    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.

Advice: Just know your code better , and relax . If you don't anything he will tell you and explain .
  1. 1
    What have you used for security
    Times asked 2
    Official solution

    SimplePassword DB mein plain text mat rakho — hash store karo jo reverse nahi hota.

    from werkzeug.security import generate_password_hash, check_password_hash
    user.password = generate_password_hash(request.form['password'])
    check_password_hash(user.password, form_password)

    Hashing ≠ encryption. Leak pe bhi original password nahi milta (easy passwords rainbow table se — isliye salt + strong hash).
    Column String(200) kyunki hash lamba hota hai. unique=True password pe mat lagao.

Advice: do all the questions in the sheet for th same proctor and have thorough knowledge of your code.
  1. 1
    Proctor Behaviour: Cool, Calm , talks softly
    Times asked 2
    Official solution

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

  2. 2
    Demo of the whole app first.
    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. 3
    How did you implement it? (Explain the 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.

  4. 4
    Explain the Database Schema.
    Times asked 1
    Official solution

    Simplemodels.py har table ki class hai — columns, PK/FK, relationships. Yeh Model layer hai.

    Viva mein file khol ke bolo:
    1) Kaunsi classes/tables hain (User, Role-specific, Booking...)
    2) Har table ka kaam 1 line
    3) Relationships: 1-1 / 1-M / M-M, backref, cascade, lazy
    4) Constraints: unique email, nullable, default status

    Example skeleton

    class User(db.Model):
        id = db.Column(db.Integer, primary_key=True)
        email = db.Column(db.String(120), unique=True, nullable=False)
        role = db.Column(db.String(20), default='user')
        bookings = db.relationship('Booking', backref='user', cascade='all, delete-orphan')

    ER diagram: rectangles entities, lines relationships, PK/FK mark. Schema = yahi structure.
    Tables create: db.create_all() ya migrations. SQLite file SQL viewer se dikha sakte ho.

  5. 5
    Name them
    Times asked 2
    Official solution

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

  6. 6
    What are you using for authentication? (JWT)
    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
    Explain the working of JWT in your 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. 8
    Is Admin authorised or authenticated?
    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)
  9. 9
    What is a Component?
    Times asked 2
    Official solution

    Definition style question: 1 line simple Hinglish + project example + mini code.

    Template'X ka kaam Y hai. Mere project mein Z jagah use hua.'

    Example'Session login state rakhta hai. session[user_id]=u.id login pe, logout pe session.clear().'

    Agar topic Vue/Celery/Redis ho aur project mein nahi hai to sach bolo, theory example do.

  10. 10
    Can you make it responsive without using CSS?
    Times asked 2
    Official solution

    Yeh live UI/CSS change hai. Examiner jo element bole uski CSS turant badlo.

    Bootstrap class badlo (btn-primary → btn-success, bg-dark → bg-warning) ya inline style='color:red; background:#eee'.
    Center: d-flex justify-content-center text-center. Navbar neeche: navbar fixed-bottom.

    Example

    <button class='btn btn-success' style='background:#16a34a'>Book</button>

    Pehle browser inspect karke class dhundo, phir template mein change karke refresh.

  11. 11
    If you had to implement search suggestions in your code, what would be your approach?
    Times asked 1
    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()
  12. 12
    Code Changes: The Username and Password field in my Login page, he asked me to shift them to the exact centre of page.
    Times asked 2
    Official solution

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

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