Exact Match

What is Exact Match?

Exact match requires query terms (or a quoted phrase) to appear exactly in the document or field—typically with no stemming, no fuzziness, and no synonym expansion. It’s often implemented as a separate, high-precision field or a phrase query operator.

How It Works (quick)

• Keyword fields: Index a keyword/untouched version of important fields (SKU, brand+model).
• Phrase queries: Support quotes " and proximity operators for titles.
• Analyzers: Disable stemming/expansion; preserve case/diacritics where needed (brands).
• Blending: Try exact first; if empty, fall back to standard matching (BM25 + fuzzy + synonyms).
• Boosting: Give exact hits a controlled boost, not an absolute pin.

Why It Matters in E-commerce

• Code searches: SKUs/MPNs/GTINs, model numbers.
• Brand integrity: Exact casing/spacing (e.g., GORE-TEX).
• User control: Quotes force strict matches when shoppers want precision.

Best Practices

• Provide quoted search and explain it in help/tooltip.
• Keep SKU/MPN in dedicated, exact fields; index normalized variants too.
• Cap the exact-match boost to avoid burying clearly better items.
• Combine with bigram/phrase fields for natural phrases.
• Log when exact matches suppress broader relevance; tune weights.

Challenges

• Typos & variance: Exact match misses near-misses; keep graceful fallback.
• Over-boosting: Can promote irrelevant clones if not capped.
• Locale issues: Accents/case in brand names need careful analyzers.

Examples

• Query "air max 270" → prioritize exact phrase in titles/attributes.
• Query SKU: AB-1234 → match the SKU keyword field exactly.
• Query "merino base layer" → exact phrase, then fall back to bigrams/unigrams.

Summary

Exact match gives shoppers precise control for codes and quoted phrases. Use dedicated fields, modest boosts, and reliable fallbacks so strict matching helps without hurting overall relevance.