Proctor Level2 Viva Proctor 785

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

Simplevenv activate → dependencies → DB create/migrate → flask run. Browser pe localhost dikhao.

Example

python -m venv .venv
source .venv/bin/activate
pip install -r requirements.txt
flask run

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

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

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

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)

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

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

SimpleProject overview: problem → roles → main entities → key flows (register, book, admin approve).

Viva tip1 minute elevator pitch ready rakho, phir demo.

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.

SimpleExaminer submitted ZIP chahta hai, local extra changes nahi.

Portal se ZIP download → extract → venv → pip install -r requirements.txt → flask run / python app.py.
Checksum maange to hash match karke dikhao. Camera/OPPE setup unke instructions.
Linux/Mac: paths, gunicorn; Windows paths alag ho to relative paths use karo.
Do browsers: admin + user parallel demo impressive lagta hai.

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.

SimpleRoutes/controllers URLs handle karte hain. app.py app banata hai, models.py data, templates/ views, static/ CSS-JS.

Typical structure:
app.py / __init__.py → Flask app, db.init, register blueprints
models.py → tables
routes.py / views → @app.route functions
templates/ → Jinja HTML
static/ → css, images
instance/*.db → SQLite

Ek route explain karne ka template:
1) URL + methods 2) Auth/role check 3) Form/query se data 4) Business rule (duplicate, slots) 5) db.session 6) render ya redirect

Example GET+POST same route: GET form, POST save.
Data HTML se: form name= → request.form. Data HTML ko: render_template(..., items=query).
Nayi .py file: import karke use karo, warna Flask ko pata nahi. Folder rename: imports/paths/templates check.

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.

Examiner code pe ungli rakh ke poochta hai — panic mat karo, 4-line formula bolo.

1) Yeh file/line kya role hai (model / route / template / config)?
2) Input kahan se aata hai (form, URL <id>, session, JSON)?
3) DB pe kya query/write?
4) Output kya (render_template / redirect / jsonify)?

Example

@app.route('/book/<int:id>', methods=['POST']) — logged-in user session se, trek id URL se, Booking add, slots--, redirect history.

Unknown line: imports (request, url_for, flash), decorators, if checks, commit — har keyword ka reason ready rakho.

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.

SimpleMVC = Model-View-Controller. Code ko 3 hisson mein baant ta hai taaki mix na ho.

Model: data + DB. models.py — User, Trek, Booking classes.
View: jo user dekhta hai. templates/*.html + Jinja.
Controller: beech ka logic. routes / app.py — request lo, model se data, view ko do.

Example flow (register):
Browser form POST → Controller register() → User model save → redirect → View dashboard.html

Draw: Browser → Controller → Model → DB, phir Controller → View → Browser.
ORM na ho to bhi MVC ho sakta hai — Model raw SQL functions ho sakte hain. Structure matter karta hai, library nahi.
MVP/MVVM doosri architectures hain; MAD1 mein MVC expected hai.

Simpledono SQLAlchemy relationships ko do taraf se connect karte hain, farq sirf likhne ke style ka hai.

backref: relationship ek side pe likhte ho, doosri side SQLAlchemy khud bana deta hai. Short hai, lekin dono models dekh ke relationship clearly nahi dikhti.

back_populates: dono models pe relationship explicitly likhte ho. Code padhne wale ko turant samajh aa jaata hai ki User.posts aur Post.author linked hain.

Example

class User(db.Model):
    posts = db.relationship('Post', backref='author')

Yahan Post.author automatically mil jaata hai.

Explicit version:

class User(db.Model):
    posts = db.relationship('Post', back_populates='author')
class Post(db.Model):
    author = db.relationship('User', back_populates='posts')

Viva tipexaminer ko bolo — MAD1 project mein back_populates zyada clear hai, isliye preferred.

SimpleCSS 3 tarikon se lagti hai, priority Inline > Internal > External (same specificity pe).

Inline: style='color:red' element pe. Highest priority, lekin reuse nahi. Debugging mushkil.
Internal: <style> tag HTML head mein. Us page tak limited.
External: style.css file. Large project ke liye best — ek jagah change, saari pages update.

Example same button pe teeno:
/* external */ .btn { color: blue; }
/* internal */ .btn { color: green; }
<!-- inline --> <button class='btn' style='color:red'> → red jeetega

ID (#box) class (.btn) se strong, class element (button) se strong.
!important sabko override karta hai — avoid karo.
Large project: external CSS preferred.

SimpleConstraints rules hain jo galat data rok te hain. Referential integrity FK valid parent ko point kare.

PK, FK, UNIQUE, NOT NULL, CHECK (age >= 18). ORM Column flags yahi map karte hain.
SQL = language tables se baat. Database organized data store.
SQL View: saved query, table jaisi dikhti hai, data copy nahi.
Cluster: kai DB servers together (HA/scale) — MAD1 SQLite single file.
Entity mapping: class User → table user, attributes → columns.

SimpleJSON = JavaScript Object Notation — data exchange ka text format.

{"name": "Ram", "age": 20}
APIs, localStorage, Chart.js data. Python dict ↔ JSON.
Structured data: tables, fixed schema (SQL). Unstructured: images, logs, free text. JSON semi-structured.
SQL structured relational. Mongo unstructured/document.

SimpleJavaScript browser pe chalta hai — click, validation, Chart.js, Bootstrap modal.

Frameworks: Vue, React, Angular. MAD1 mein vanilla JS / Bootstrap JS kaafi.
Modal: popup overlay. Bootstrap: data-bs-toggle='modal' data-bs-target='#id'.
Flash hide: setTimeout se alert remove. Form submit confirm: onsubmit='return confirm(...)'.
Agar project mein JS kam hai to sach bolo, theory example do.

SimpleVertical = same machine ko powerful banao. Horizontal = aur machines add karo.

Vertical (scale up): RAM/CPU badhao. Simple, lekin ek limit hai, downtime ho sakta hai, single point of failure.
Horizontal (scale out): 5 servers + load balancer. Sasta long-term, fault tolerant, lekin session/DB sharing sochna padta hai.

Example10k users aaye to Flask app ke 4 copies chalao nginx peeche, DB alag machine pe.

Thousands of requests on one machine: caching (Redis), DB indexes, gunicorn workers, phir horizontal.

SimplePrimary Key row ki unique ID hai, Foreign Key doosri table ki Primary Key ko point karti hai.

Primary Key: unique + not null. Har table mein hota hai. Example: user.id = 5
Foreign Key: relationship banati hai. post.user_id = 5 matlab yeh post user 5 ki hai.

Example

class User(db.Model):
    id = db.Column(db.Integer, primary_key=True)
class Post(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    user_id = db.Column(db.Integer, db.ForeignKey('user.id'))

FK Primary Key bhi ho sakti hai (1-to-1 profile table). FK unique ho to One-to-One, nahi to One-to-Many.

Simplelazy loading related objects tab load karta hai jab attribute access karte ho, pehle nahi.

user = User.query.get(1)  # posts query nahi

user.posts # ab query

lazy=True / 'select' default. lazy='joined' eager join. lazy='dynamic' query object.
uselist=False One-to-One (single object, list nahi). Hataoge to list mil sakti hai.
Frontend lazy loading images alag cheez hai (viewport mein aaye tab load).

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.

SimpleHTTP methods batate hain request kya karna chahti hai. Common: GET POST PUT PATCH DELETE.

GETread/fetch. Safe, URL se. Page kholna, search.

POSTcreate/submit. Form, login.

PUTpoora replace/update. Idempotent.

PATCHpartial update.

DELETEhataana.

HEAD: sirf headers. OPTIONS: CORS preflight.

Flask: @app.route('/x', methods=['GET','POST'])
Agar methods na likho to default sirf GET.
HTML form native sirf GET/POST. PUT/DELETE JS/fetch ya hidden _method se.
GET se data fetch ho sakta hai, create nahi karna chahiye. POST se theoretically fetch ho sakta hai lekin cache/semantics galat.
DELETE fetch ke liye nahi. GET POST ka kaam officially nahi karta — side effects GET pe mat rakho.

SimpleSQL Injection user input ko SQL bana ke DB hack. ORM/parameterized queries se bachao.

Galat: f"SELECT * FROM user WHERE email='{email}'" # email = ' OR 1=1 --
Sahi: User.query.filter_by(email=email) # bound parameters
Raw: db.session.execute(text('SELECT * FROM user WHERE id=:id'), {'id': i})
Extra: least privilege DB user, input validate, error messages generic.

Simplerender_template HTML file ko Jinja se process karke browser ko bhejta hai. Backend data ko frontend se jodta hai.

return render_template('dashboard.html', user=user, treks=treks)

File templates/dashboard.html honi chahiye.
Keyword arguments template mein variables ban jaate hain: {{ user.name }}.
Route kuch return na kare to Flask error. Boolean return typical HTML view ke liye nahi — string/Response chahiye.

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.