𝗣𝗵𝗮𝘀𝗲 𝟭: 𝗗𝗼𝗰𝘂𝗺𝗲𝗻𝘁 𝗜𝗻𝗴𝗲𝘀𝘁𝗶𝗼𝗻

Most RAG systems fail before they even start.

You think building a RAG system is simple. A user uploads a PDF, you create embeddings, and you get answers.

That is a mistake.

Between the upload button and the vector database, there are 15 critical steps. If you skip one, your system gives wrong answers or wastes your money.

Here is the production-grade roadmap for document ingestion:

• File Hashing: Never hash the filename. Hash the actual file content. This stops your system from processing the same file twice if someone renames it.

• Smart Parsing: Use the right tool for the job.

  • Simple text: pdf-parse (Free)
  • Mixed content: Unstructured (Balanced)
  • Complex tables/layouts: LlamaParse (High quality)
  • Enterprise forms: Azure Document Intelligence (Best for scans)

• Text Cleaning: Remove the junk. Headers, footers, watermarks, and page numbers create noise. If you embed "Confidential" on every page, your AI will think every answer is a secret.

• Metadata Extraction: Add context like department, section, or version. This helps your system find the right document without searching everything.

• Smart Chunking: This is the most important part.

  • Size: Aim for 1000 to 1500 tokens.
  • Overlap: Use 200 tokens of overlap to keep context.
  • Boundaries: Never break a sentence in the middle.

• Chunk Hashing and Deduplication: Hash every chunk. When a file changes, compare the new hashes to the old ones.

• Incremental Ingestion: Do not re-embed everything. If a 1000-page document changes by only one page, only embed that one new chunk. This saves you massive amounts of money on API costs.

The difference between a hobby project and a production system is the work you do before the embedding step.

A naive system re-embeds everything every time. A smart system only processes what changed.

Stop building soup. Build a foundation.

Source: https://dev.to/surajrkhonde/phase-1-document-ingestion-the-hidden-complexity-before-embeddings-4d32

Optional learning community: https://t.me/GyaanSetuAi