Field collapsing
/ Collapse, / Deduplication, / SearchField collapsing #
Collapse the result list so each distinct value of a field appears at most once — “best product per merchant”, “best article per author” — without a terms aggregation, keeping full hit semantics (scores, source, highlight).
POST /my-collection/_search
How it works #
Collapse is engine-native and runs as a post-retrieval step. The collector
normally stops at from + size, but collapse pages over GROUPS, so the
engine first gathers a wider window — max(1000, from + size) hits
(COLLAPSE_WINDOW in lib/engine/src/search/mod.rs) — in request sort
order, then: