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FDE 101

Query rewriting

Query rewriting transforms a user’s question into wording that a search system may retrieve more effectively. A rewrite may add corpus terminology, correct spelling, resolve conversation references, or create several focused queries.

Tiny example

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User:     Can I send it back after two weeks?
Rewrite:  return policy after 14 days

The rewrite matches likely policy language. It might also lose an exact order ID or misunderstand what “it” means.

Safe pattern

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Search with the original query and one or more rewrites, record each version, and compare retrieval quality with and without rewriting. Microsoft’s query-rewrite documentation follows this original-plus-rewrites pattern and warns about losing exact terms such as product codes.1

FDE note

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Rewriting adds another fallible model operation, latency, and cost. Use it for a measured query-understanding problem, not as a mandatory RAG stage.

Footnotes

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  1. Microsoft, query rewriting in Azure AI Search. The documented API is vendor-specific and currently preview. ↩