Full-text Search

Full-text search lets you find nodes by the words in their string properties. Omnigraph provides four text search expressions: search() for keyword matching, fuzzy() for typo-tolerant matching, match_text() for a dedicated text-match call site, and bm25() for relevance ranking.

Schema setup

Text search requires an @index annotation on a String property. This causes Omnigraph to build an inverted index over that field when data is loaded.

node Article {
    slug:  String @key
    title: String @index
    body:  String @index
}

node Person {
    name: String @key
    bio:  String @index
}

Without @index, queries that reference search(), fuzzy(), match_text(), or bm25() on that field are rejected at compile time.

search() — keyword matching

search(field, term) appears in the match block and filters to nodes whose indexed field contains the search term.

query find_articles($term: String) {
    match {
        $a: Article
        search($a.title, $term)
    }
    return { $a.slug, $a.title }
}

fuzzy() — typo-tolerant matching

fuzzy(field, term, distance) works like search() but allows matches within a given edit distance. The third argument is optional and defaults to 2.

query fuzzy_search($term: String) {
    match {
        $p: Person
        fuzzy($p.name, $term, 2)
    }
    return { $p.name }
}

match_text() — current text-match behavior

match_text(field, phrase) is a separate query expression, but in the current runtime it uses the same Lance full-text backend as search(). Treat it as tokenized text matching, not strict phrase adjacency.

query phrase_search($phrase: String) {
    match {
        $a: Article
        match_text($a.body, $phrase)
    }
    return { $a.slug, $a.title }
}

bm25() — relevance ranking

bm25(field, term) appears in the order block and ranks results by BM25 relevance score.

query ranked_articles($term: String) {
    match {
        $a: Article
        search($a.title, $term)
    }
    return { $a.slug, $a.title }
    order { bm25($a.title, $term) desc }
}

Combining search with traversal

Search expressions compose naturally with graph traversal. You can filter by text, traverse edges, and return properties from connected nodes:

query articles_by_author($term: String, $author: String) {
    match {
        $a: Article
        search($a.title, $term)
        $a writtenBy $p: Person { name: $author }
    }
    return { $a.slug, $a.title, $p.name }
    order { bm25($a.title, $term) desc }
}