RAG: The Secret Sauce for Sharper, Smarter AI

Shruti Sharma
7 min readSep 2, 2024

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“Large Language Models (LLMs) — they’re the wunderkinds of the AI world. They’re everywhere, popping up in chatbots, search engines, and even helping you draft those tricky emails. “

Source : https://serokell.io/blog/language-models-behind-chatgpt

LLMs like that one mate of yours who’s a trivia genius but occasionally blurts out something hilariously off the mark. One moment they’re astonishingly accurate, and the next, they’re confidently misinforming you about the number of moons around Jupiter.

But wait, there’s more! Meet RAG, a framework designed to help our dear LLMs be a little less like your overly confident trivia friend and more like the reliable, well-read acquaintance who always checks their facts.

Let’s take you on a quirky little journey through Retrieval-Augmented Generation. Or as we like to call it, RAG.

What is RAG?

So, what exactly is RAG? Let’s break it down. We’ll start by focusing on the “Generation” part. This refers to the LLM’s ability to generate text in response to a user query, which we fancy folks call a “prompt.” Picture this: you ask your model a question, and it spits out an answer. Simple, right? Well, not always.

Source : https://www.datacamp.com/blog/what-is-retrieval-augmented-generation-rag

Here’s where it gets interesting — LLMs, despite their encyclopedic training, can sometimes behave like that know-it-all kid who raises their hand in class before the question is fully asked.

They might get it right, or they might boldly deliver an answer that’s wildly off-base. Here’s an anecdote to illustrate the point.

The RAG Model

Source : https://www.bentoml.com/blog/building-rag-with-open-source-and-custom-ai-models
  • Chunking: The process starts by transforming your structured or unstructured data into text documents and dividing the text into smaller segments, or chunks.
  • Embedding Documents: A text embedding model is then used to convert each chunk into vectors that capture their semantic meaning.
  • VectorDB: These embeddings are stored in a vector database, which forms the basis for data retrieval.
  • Retrieval: When a user query is received, the vector database retrieves the chunks most relevant to the query.
  • Response Generation: Using this context, a large language model (LLM) synthesizes the retrieved chunks to produce a coherent and informative response.

While setting up a basic RAG system with a text embedding model and an LLM might require only a few lines of Python code, handling real-world datasets and optimizing system performance demands more advanced techniques.

An Anecdote: When Coffee Gets you buzzin!

Imagine me confidently telling my friends at a dinner party, “You know, coffee actually dehydrates you more than it hydrates you!” Feeling like a health guru, I bask in their impressed nods.

But here’s the kicker: as I sip my third cup, someone casually mentions, “Actually, that’s not true — coffee does contribute to your daily water intake.” Yikes! My bold declaration, though said with the conviction of a wellness expert, was outdated and completely off the mark.

It was a bit too exaggerated, and I didn’t double-check my sources. Classic LLM blunder, right? This brings us to two big problems that LLMs often face: no sources and outdated information.

How Would an LLM Handle This?

If you asked a large language model about coffee’s effects, it might confidently repeat that old myth about dehydration. It’s like the model saying, “Trust me, I read this in a dusty old study!” But here’s the problem: just like me at that dinner party, the model doesn’t realize it’s spreading outdated or incorrect information.

The LLM doesn't have the ability to fact-check in real-time and might even be wrong in worst case scenarios, so it could end up giving you a slightly off answer, all with a convincing tone. That’s where things get tricky—accurate-sounding, but not always spot-on.

From RAG to Riches

So, how does RAG swoop in to save the day? Here’s the magic: Retrieval-Augmented Generation enhances the LLM’s capabilities by adding a content store. Think of this as the model’s personal library or database, packed with up-to-date and relevant information.

Source : https://graphql.com/learn/what-is-graphql/

Before the LLM answers your question, it consults its trusty content store, asking, “Hey, can you fetch me the latest and most accurate info?” With this retrieval step, the model doesn’t just rely on its potentially outdated training data — it checks current, reliable sources first.

Why Does This Matter?

Remember those two problems — outdated information and lack of sources? RAG addresses both by:

  • Keeping it Current: No need to retrain the model every time a new moon is discovered. Just update the content store, and voila! The next time you ask, “Which planet has the most moons?”, the model will accurately tell you, “Saturn, with 146 moons — for now!”
  • Sourcing Smarts: Instead of the model relying solely on what it “remembers,” it now cites primary sources. This reduces the chances of it hallucinating information or confidently spouting incorrect facts. It also gives the model the humility to say, “I don’t know” when it genuinely doesn’t have enough information — a trait we could all benefit from, LLM or human.

The Double-Edged Sword of RAG

But RAG isn’t without its challenges. The quality of the retrieval process is crucial. If the retriever fetches subpar information, the model’s response might be lackluster or incomplete :

  1. Key Challenges in Retrieval: RAG systems often face challenges during the retrieval phase, such as handling ambiguous terms and matching queries based on broad similarities rather than specific details.
  2. Augmentation Limitations: The augmentation phase may struggle with adequately contextualizing retrieved data, leading to superficial or incomplete responses.
Source : https://www.effectivedatastorytelling.com/post/contextualized-insights-six-ways-to-put-your-numbers-in-context

3. Generation Phase Issues: Flaws in retrieval or augmentation can result in inaccurate or contextually off-target generated responses, exacerbated by token limits and the order of information presentation.

4. Latency Concerns: RAG systems can introduce additional latency in real-time applications, necessitating optimization techniques like caching and parallel processing.

That’s why teams at IBM and beyond are tirelessly working on both sides of the equation — improving the retrievers and fine-tuning the generative models.

Source : https://the-decoder.com/here-is-an-interesting-take-on-llm-hallucinations-by-andrej-karpathy/

There have also been considerable discussions about the tendency of LLMs to produce hallucinations, where their responses to user queries may appear convincing but are factually incorrect, as discussed in the previous section.

Streamlining RAG Architectures with Cortex Search

Addressing these limitations involves advanced techniques like word sense disambiguation, multi-hop reasoning, query decomposition, and latency optimization to enhance RAG system performance.

  • Managed Vectors and Retrieval: Cortex Search simplifies the implementation of Retrieval Augmented Generation (RAG) architectures, enabling organizations to bring private, up-to-date information to LLMs for more accurate results.
  • Document Retrieval: Cortex Search fetches relevant documents or passages from a knowledge source based on the input question.
  • LLM Integration: The retrieved information is then passed to an LLM in Snowflake Cortex, generating accurate and contextually relevant responses.

Productive & Enhanced Use Cases

  • RAG-based Chatbots: Cortex Search simplifies the development of RAG-based chatbots, increasing team productivity by efficiently searching through large document corpora.
End to End Rag, Source : https://www.snowflake.com/en/blog/easy-secure-llm-inference-retrieval-augmented-generation-rag-cortex/
  • Applications:
  1. Needle-in-a-haystack Lookups: Quickly find specific answers hidden within vast amounts of documents.
  2. Multidoc Synthesis and Reasoning: Source answers from information spread across multiple documents.
  3. Tabular Data and Figure Synthesis: Retrieve answers from structured data such as databases and spreadsheets.

Simplifying LLM Customization with Cortex Fine-Tuning

  • Fine-Tuning Models: Cortex Fine-Tuning allows you to customize industry-leading models from Meta and Mistral AI, improving accuracy for specific tasks like summarization.
  • Cost Efficiency: Fine-tune a smaller base model to achieve the same accuracy as larger models, reducing inference latency and costs.
  • Ease of Use: Fine-tune models by calling an API or SQL function without managing any infrastructure. Once the fine-tuned model is ready, it can be seamlessly integrated into your application with secure access controls.
Source : https://docs.snowflake.com/en/guides-overview-ml-powered-functions

Delivering Value with Prompt Engineering and RAG

  • Strategic Use Cases: Identify and deploy use cases that deliver quick wins using prompt engineering and RAG for fast, cost-effective results from enterprise data with LLMs.
  • Public Preview Availability: Snowflake Cortex LLM functions are now in public preview for select AWS and Azure regions, offering a fully managed service with NVIDIA GPU-accelerated compute.

RAG is the Future

In a world where information is constantly evolving, RAG is helping large language models keep up, ensuring they’re not just confident but also accurate. Whether it’s telling you about moons or answering your burning questions, RAG is a game-changer in the AI landscape.

So next time you chat with an AI, remember — it might just be a little smarter, thanks to RAG.

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