Introduction to RAG for LLMs: Sparse (Lexical) RAG and Dense RAG (Semantic Vector Search)

Introduction LLMs store information within their own parameters. By being trained on massive datasets, the models learn this data. But what if they are asked about the information they don't know? These queries will likely result in hallucinations or entirely wrong answers. As we know, updating the models with current data is very difficult and resource-intensive. Therefore, most AI service providers do not update their models frequently. Instead, they usually leave the models as they are after