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Viva Prep

Prepare in structure for the Project Mentorship.

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Lazy IITians

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Question sets

  1. 1
    mutation vs action
    Times asked 1
    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.

  2. 2
    write a query to fetch the jobs created by the company google
    Times asked 1
    Official solution

    Simplefilter manager_id / company name / approved. Same Query API. Write query fetch treks/jobs/drives.

    Examiner project-specific names — same pattern.

    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: Drive.query.filter_by(approved=True)

  3. 3
    write template and script such that user takes 2 inputs say firstname and lastname. add a button. upon clicking, it should return firstname+lastname.
    Times asked 2
    Official solution

    SimpleVue live: two inputs v-model, button @click se first+last concat karke dikhao.

    Example

    <input v-model="first" /><input v-model="last" />
    <button @click="full = first + ' ' + last">Go</button>
    <p>{{ full }}</p>
Advice: Go through your entire code. He checks if we understand which thing is written for what.
  1. 1
    • ID verification.
    Times asked 2
    Official solution

    SimpleCamera pe clearly IITM/college ID dikhao — naam photo match.

    Pehle se ID haath mein rakho. Glare mat aane do. Examiner screenshot/verify karta hai. Iske baad GitHub + project run.

  2. 2
    • Explained the viva process and gave permission to start.
    Times asked 2
    Official solution

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

  3. 3
    • What is template inheritance?
    Times asked 1
    Official solution

    SimpleBase template pe navbar/footer, child pages {% extends %} + {% block %} se content bharte hain. DRY.

    Example

    {# base.html #}
    {% block content %}{% endblock %}
    
    {# home.html #}
    {% extends 'base.html' %}
    {% block content %}
      <h1>Home</h1>
    {% endblock %}
Advice: Very calm and supportive proctor. He first explains the complete viva process, so don't panic. Keep your project ready because he asks for a complete demo followed by a detailed code explanation. Explain your project confidently without waiting for interruptions, as he mostly listens. Know your backend code well, especially authentication, JWT, Redis, Celery, and your project flow. Revise common theory questions like browser storage, template inheritance, Flask endpoints, and authentication vs authorization. If you explain your project clearly and confidently, the viva goes very smoothly.
  1. 1
    Diff between cell spacing and cell padding
    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.

  2. 2
    Status codes mean - 201, 301, 401, 501 That's it - i didn't even complete my presentation, he said you've done well and can leave the call. it only lasted for half an hr.
    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.

Advice: br confident and explain clearly
  1. 1
    Update code of search bar such that while searching using email ,if I write '@gmail.com' then it should not show any data . Search email only based on string before @ .
    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()
  2. 2
    Difference between local storage and session storage. I used local storage so he asked that your app will be in danger if the data is stored locally even after refresh . Anyone can see credentials locally.
    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
    What is cache.cached and cache.memorize
    Times asked 2
    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.

  4. 4
    What is decorator and why we use decorator not functions.
    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
  5. 5
    Why you have used jsonify
    Times asked 2
    Official solution

    Simplejsonify Python dict/list ko JSON response + proper Content-Type deta hai.

    Example

    return jsonify(message='ok', count=3), 200
  6. 6
    What are derivatives He basically go through my whole code and ask questions from anywhere. Some more questions were asked. I don't remember those.
    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.

Advice: He is a chill person . Take your time while updating code question. Ask mostly questions from your code.
  1. 1
    asked to show 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.

  2. 2
    what is onmounded()
    Times asked 1
    Official solution

    SimpleonMounted / mounted = component DOM pe aa gaya. Yahan API fetch, Chart init. (Typo onmounded = onMounted)

  3. 3
    what are different types of vue life cycle hooks
    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.

  4. 4
    vue code to add two numbers and display a message
    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
    python code to fetch all the trek which have difficulty level set easy 9.why do we use caching
    Times asked 1
    Official solution

    SimpleCache isliye taaki 100 users same dashboard pe DB ko 100 baar na maror dein.

    Problem: repeated reads, slow page, extra load. Cache seconds ke liye snapshot deta hai.

    Nahi use karna: har second badalne wala live stock, user-private secret data bina soch ke (key mein user_id hona chahiye).

    Memoization caching ka subset hai (function args). HTTP 304 / browser cache alag layer.

    Redis in-memory key-value store hai — fridge pe sticky note, poori kitchen (SQL database) har baar mat kholo.

    MAD2 mein Redis do kaam: (1) cache — same venues/shows/dashboard JSON baar-baar DB se nahi (2) Celery broker — Flask task queue mein daalta hai, worker uthata hai.

    Flow: cache.get(key) → hit pe return, miss pe SQLAlchemy + SET with timeout. Admin write ke baad cache.delete, warna stale list.

    Source of truth database hi hai. Redis crash/band = cache miss (app chalni chahiye) + queue ruk sakti hai. Important bookings sirf Redis mein mat rakho.

    Alag: Redis ≠ Memcached (Celery broker nahi). Redis ≠ localStorage (woh browser). redis-cli ping → PONG viva proof.

    Project example: Shows list har user dekhta hai — perfect cache. Booking POST cache nahi — har baar write.

Advice: he is very nice I messed up while starting my application process as i opend the wrong folder so he gave me type to redo everything and gave me time . he is not that responsive he gave me q to code and i was sitting there i thought he will see it and say something but he didn't i had to tell him i am done. he then told me that don't be nervous for viva 2 and asked my name and were i am from and stuff like that - over all hes very sweet and nice , will not grind you too much as simple question ehich u can answer in layman term .
  1. 1
    Write a code to create a table name "report" with,id ,name and is_generated..in notepad
    Times asked 2
    Official solution

    SimpleNaya Flask route: URL, method, auth if needed, query, jsonify. Postman pehle.

    Examiner number/filter change easy rakhna. CORS. Frontend tabhi jab bole.

    Status codes sahi. Password JSON mein nahi.

    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.

    Example

    @app.route('/api/sum', methods=['POST'])
    def sum_num():
        d = request.get_json()
        return jsonify(result=d['a'] + d['b'])

    Project example: resources.py new Resource. Test Thunder. Optional Vue fetch.

  2. 2
    Difference between cache and redis.
    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.

  3. 3
    What type of authentication you have used?
    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)
  4. 4
    And some more easy questions.
    Times asked 2
    Official solution

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

Advice: I think it was my luckiest day that I got him as my proctored.He was so calm and sweet ,talked very nicely , he corrected all my mistakes and at last he said all the best for level2 and also said that they will ask more tough questions so be prepared and he suggest me to practice coding questions as well..agar koi dusra Banda rahta to main fail thi..
  1. 1
    Explain lifecycle
    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
    How they communicate ( question was like that but I forgot exactly what it was )
    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.

  3. 3
    A term which I never heard so I dont remember
    Times asked 2
    Official solution

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

  4. 4
    Some follow up questions.
    Times asked 2
    Official solution

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

Advice: He is good.
  1. 1
    What is cascade
    Times asked 2
    Official solution

    SimpleCascade parent ke saath child pe automatic action (generally delete).

    Company delete → uski drives bhi delete, warna orphan rows / FK error.
    SQLAlchemy: db.relationship('Drive', cascade='all, delete-orphan', backref='company')
    SQL: ForeignKey(..., ondelete='CASCADE')

    Cascade sirf delete nahi: save-update, merge, refresh-expire, expunge, delete-orphan.
    Cascade Update: parent PK change to child FK update (rare, PK mat badlo).
    Parent delete jab children active hon: constraint error, ya cascade se children gayab, ya pehle children handle karo — design choice examiner poochta hai.
    CSS cascading alag topic hai (styles inherit/override).

  2. 2
    lifecycle hooks and where you have used them
    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.

  3. 3
    write an api route to compile the list of completed treks
    Times asked 2
    Official solution

    SimpleLive Flask coding: chhota route likho, save, browser/curl se test. Syntax error terminal mein padho.

    Example

    @app.route('/ping')
    def ping():
        return jsonify(ok=True)
    
    @app.route('/even/<int:n>')
    def even(n):
        return 'even' if n % 2 == 0 else 'odd'
Advice: he is very chill. i had some trouble running the app, and he gave me extra time to figure out the errors. he asks the same questions as in the sheet
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