This version is still in development and is not considered stable yet. For the latest stable version, please use Spring Data Neo4j 8.0.0!spring-doc.cn

Neo4j Vector Search

The @VectorSearch annotation

Spring Data Neo4j supports Neo4j’s vector search on the repository level by using the @VectorSearch annotation. For this to work, Neo4j needs to have a vector index in place. How to create a vector index is explained in the Neo4j documentation.spring-doc.cn

It’s not required to have any (Spring Data) Vector typed property be defined in the domain entities for this to work because the search operates exclusively on the index.

The @VectorSearch annotation requires two arguments: The name of the vector index to be used and the number of nearest neighbours.spring-doc.cn

For a general vector search over the whole domain, it’s possible to use a derived finder method without any property.spring-doc.cn

interface VectorSearchRepository extends Neo4jRepository<EntityWithVector, String> {

    @VectorSearch(indexName = "entityIndex", numberOfNodes = 2)
    List<EntityWithVector> findBy(Vector searchVector);

}

The vector index can be combined with any property-based finder method to filter down the results.spring-doc.cn

For technical reasons, the vector search will always be executed before the property search gets invoked. E.g. if the property filter looks for a person named "Helge", but the vector search only yields "Hannes", there won’t be a result. 
interface VectorSearchRepository extends Neo4jRepository<EntityWithVector, String> {

    @VectorSearch(indexName = "entityIndex", numberOfNodes = 1)
    List<EntityWithVector> findByName(String name, Vector searchVector);

}