Use OCR and page-level chunking.
Structure Preservation: OCR combined with document layout analysis (such as layout-aware or page-level chunking) detects visual structures like tables, headers, and reading order.
Row-Level Granularity: Page-level chunking retains the boundaries and context of multipage tables, enabling the RAG system to isolate and retrieve specific rows effectively.
Metadata Enrichment: Processing documents page-by-page allows the ingestion pipeline to automatically tag each extracted text chunk with its source page-number metadata.
Incorrect:
[not C]
Use page-level OCR extraction and store each page as a single chunk:
While this captures page numbers, storing an entire page as a single chunk introduces too much noise. It prevents the model from pinpointing specific table rows and often exceeds the optimal context window size for precise RAG retrieval.
[Not D]
Use basic parsing and fixed-size chunking:
Basic parsing cannot read digitally scanned PDFs, resulting in empty or completely garbled text.
Furthermore, fixed-size chunking splits text at arbitrary character limits, which destroys table structures and splits individual rows across different chunks.
Reference:
https://pub.towardsai.net/unlocking-key-technologies-in-document-parsing-81bfe20d741b