22 min Intermediate Prerequisite: Fine-tuning

RAG: Retrieval Augmented Generation

LLM ko apna knowledge base do � hallucination zero, accuracy hero!

Why Learn RAG?

RAG se LLM apne knowledge base se answer deta hai � hallucination kam hota hai, fresh data milta hai. Production AI systems mein sabse zyada use hota hai.

Samjho, LLM ko library mein bitha diya � ab woh kitabon se jawab dega, yaad se nahi!

Concept Grid

RETRIEVAL

Fetch relevant documents from knowledge base

"Data dhoondna � jaise library mein book dhundhte ho"
💡

AUGMENTATION

Add retrieved context to the user query

"Context add karna � sawal ke saath kitab ka page bhi do"
💡

GENERATION

LLM generates answer using augmented context

"Answer banana � ab LLM sab kuch padh ke jawab dega"

EMBEDDING

Convert text to vector representation for search

"Numbers mein convert karna � taaki computer samjhe"

How RAG Works

User Query
Retrieve Docs
🔧
Augment Query
LLM Generate
Answer

RAG vs Fine-tuning

Dono ka fark samjho:

COMPARISON
# Fine-tuning: Model ko naya skill sikhaate ho
# Jaise: Bachhe ko French padhna sikhaana
# Result: Model naya skill seekh leta hai
# Limitation: Sirf training data tak limited

# RAG: Model ko library card dete ho
# Jaise: Bachhe ko library ka access dete ho
# Result: Model kitabon se padh ke answer deta hai
# Advantage: Naya data aaya✓ Library mein daal do!

# Practical Example:
# Company ka internal FAQ system
# - Fine-tune: Har naya question pe retrain karo ?
# - RAG: Naye docs daal do, auto-update ?

RAG Pipeline Components

Ek complete RAG system mein ye sab hota hai:

ARCHITECTURE
# 1. Document Store
# - PDFs, HTML, TXT, Database records
# - Chunking: Bade documents ko chhote pieces mein todo

# 2. Embedding Model
# - Text ✓ Vector (numbers)
# - Examples: all-MiniLM-L6-v2, text-embedding-ada-002

# 3. Vector Database
# - Vectors store karo + search karo
# - Examples: FAISS, Pinecone, Weaviate, ChromaDB

# 4. Retrieval Logic
# - Query embed karo
# - Similar documents dhoondo
# - Top-K results lo (jaise top 3)

# 5. LLM with Context
# - Prompt mein context daalo
# - LLM se answer generate karao

Code Example: Simple RAG

PYTHON
# Simple RAG with FAISS
from sentence_transformers import SentenceTransformer
import numpy as np

# Knowledge base
documents = [
 "DSWallah ek learning platform hai",
 "Python beginner ke liye best hai",
 "Machine Learning se predictions hoti hain",
 "Data Science mein statistics important hai",
]

# Embed
model = SentenceTransformer('all-MiniLM-L6-v2')
doc_embeddings = model.encode(documents)

# Query
query = "Kya sikhein data science mein?"
query_embedding = model.encode(query)

# Search
similarities = np.dot(doc_embeddings, query_embedding)
best_idx = np.argmax(similarities)
print(f"Most relevant: {documents[best_idx]}")
print(f"Query: {query}")
print("Answer based on retrieved context!")

Production RAG with LangChain

PYTHON
from langchain.document_loaders import PyPDFLoader
from langchain.text_splitter import RecursiveCharacterTextSplitter
from langchain.embeddings import OpenAIEmbeddings
from langchain.vectorstores import FAISS
from langchain.chains import RetrievalQA
from langchain.llms import OpenAI

# 1. Load documents
loader = PyPDFLoader("company_manual.pdf")
documents = loader.load()

# 2. Split into chunks
splitter = RecursiveCharacterTextSplitter(
 chunk_size=1000,
 chunk_overlap=200
)
chunks = splitter.split_documents(documents)

# 3. Create vector store
embeddings = OpenAIEmbeddings()
vectorstore = FAISS.from_documents(chunks, embeddings)

# 4. Create QA chain
qa_chain = RetrievalQA.from_chain_type(
 llm=OpenAI(),
 retriever=vectorstore.as_retriever()
)

# 5. Ask questions!
answer = qa_chain.run("Company ka leave policy kya hai?")
print(answer)

Interactive Editor

Apna RAG system build karo � code edit karo aur Run dabao!

RAG Playground
Output
Run code dekhne ke liye...

Exercise

Check Your Understanding

RAG kya hai?

LLM ko retrain karna naye data pe
Retrieval se data nikalo, phir LLM se answer generate karao
Sirf embedding banana hai
Vector database ka naam hai