Full-Text Search (@@)

The @@ operator performs BM25-scored full-text search on indexed text content.

Basic Usage

MATCH (d:Document)
WHERE d.content @@ "neural networks"
RETURN d.title

This searches all nodes that have had their text indexed with fts_index() and returns those matching the search terms.

How It Works

When the query planner encounters @@, it uses the inverted index to find matching nodes directly — no full scan needed. Results are scored using BM25, which considers term frequency, inverse document frequency, and document length.

String Queries

The search query is a space-separated list of terms. All terms must match (implicit AND):

-- Both "neural" and "networks" must appear
MATCH (n) WHERE n.text @@ "neural networks" RETURN n

Using Parameters

MATCH (d:Document)
WHERE d.content @@ $search_text
RETURN d.title

Python:

results = db.query(
    'MATCH (d:Document) WHERE d.content @@ $q RETURN d.title',
    parameters={"q": "machine learning"}
)

TypeScript:

const results = await db.query(
  'MATCH (d:Document) WHERE d.content @@ $q RETURN d.title',
  { q: "machine learning" }
);

Combining with Graph Traversal

MATCH (chunk:Chunk)-[:PART_OF]->(doc:Document)-[:AUTHORED_BY]->(author:Person)
WHERE chunk.text @@ "transformer attention"
RETURN doc.title, author.name

MATCH (chunk:Chunk)
WHERE chunk.embedding <=> $query < 0.5
  AND chunk.text @@ "transformer"
RETURN chunk.text
ORDER BY chunk.embedding <=> $query

Indexing Text

Text must be indexed before it can be searched. Use fts_index() within a write transaction:

Python:

with db.write() as txn:
    txn.fts_index(node.id, "The transformer architecture uses self-attention mechanisms")
    txn.commit()

TypeScript:

await db.write(async (txn) => {
  await txn.ftsIndex(node.id, "The transformer architecture uses self-attention mechanisms");
});

In addition to the @@ operator in Cypher, you can use the dedicated search APIs:

Python:

# Exact search
results = db.fts_search("machine learning", limit=10)

# Fuzzy search (typo-tolerant)
results = db.fts_search_fuzzy("machin lerning", limit=10)

TypeScript:

// Exact search
const results = await db.ftsSearch("machine learning", { limit: 10 });

// Fuzzy search (typo-tolerant)
const results = await db.ftsSearchFuzzy("machin lerning", { limit: 10 });