[FEATURE] Qdrant Hybrid Search

[chaucerling]

Describe the feature you'd like Qdrant is support hybrid search https://qdrant.tech/articles/hybrid-search/

[davide445]

Due I'm interested too adding here some other info:

• I'm testing on bge-m3 model that's able to generate both dense and sparse vectors. Qdrant allow two vectors to be inserted in a data point, so that we can create a single collection with both dense and sparse vectors such as in this example (created asking Claude 3.5)

const { QdrantClient } = require('@qdrant/qdrant-js');
const { pipeline } = require('@xenova/transformers');

const client = new QdrantClient({ url: "http://localhost:6333" });

async function createCollectionWithMultipleVectors() {
    await client.createCollection('text_collection', {
        vectors: {
            dense: {
                size: 1024,  //  BGE-M3 dense vector dimension
                distance: 'Cosine'
            },
            sparse: {
                size: 30522,  // BGE-M3 vocabulary dimension
                distance: 'Dot'
            }
        },
        on_disk_payload: true
    });
}

async function generateEmbeddings(text) {
    const pipe = await pipeline('feature-extraction', 'Xenova/bge-m3');
    const result = await pipe(text, { pooling: 'mean', normalize: true });

    return {
        dense: Array.from(result.dense_embeddings.data),
        sparse: {
            indices: Array.from(result.sparse_embeddings.indices),
            values: Array.from(result.sparse_embeddings.values)
        }
    };
}

async function insertTextWithMultipleVectors(text) {
    const embeddings = await generateEmbeddings(text);

    await client.upsert('text_collection', {
        wait: true,
        points: [
            {
                id: Date.now().toString(),  // Timestamp as unique ID
                vector: embeddings,
                payload: {
                    'text': text
                }
            }
        ]
    });
}

async function hybridSearch(text, limit = 5) {
    const embeddings = await generateEmbeddings(text);

    const searchResult = await client.search('text_collection', {
        vector: {
            dense: embeddings.dense,
            sparse: embeddings.sparse
        },
        limit: limit
    });

    return searchResult;
}

async function main() {
    try {
        await createCollectionWithMultipleVectors();
        console.log("Successfully created the collection");

        const text = "Text example";
        await insertTextWithMultipleVectors(text);
        console.log("Successfully inserted text");

    } catch (error) {
        console.error("There was an errror:", error);
    }
}

main();

• next creating a hybrid query in Qdrant can be done using the new api such as in this example

const { QdrantClient } = require('@qdrant/qdrant-js');
const { pipeline } = require('@xenova/transformers');
const Anthropic = require('@anthropic-ai/sdk');

const qdrantClient = new QdrantClient({ url: "http://localhost:6333" });
const anthropic = new Anthropic({
    apiKey: 'your-anthropic-api-key-here'
});

async function generateEmbeddings(text) {
    const pipe = await pipeline('feature-extraction', 'Xenova/bge-m3');
    const result = await pipe(text, { pooling: 'mean', normalize: true });

    return {
        dense: Array.from(result.dense_embeddings.data),
        sparse: {
            indices: Array.from(result.sparse_embeddings.indices),
            values: Array.from(result.sparse_embeddings.values)
        }
    };
}

async function hybridSearch(text, limit = 5) {
    const embeddings = await generateEmbeddings(text);

    const searchResult = await qdrantClient.search('text_collection', {
        vector: {
            dense: embeddings.dense,
            sparse: embeddings.sparse
        },
        limit: limit
    });

    return searchResult;
}

async function askClaude(context, question) {
    const message = await anthropic.messages.create({
        model: 'claude-3-opus-20240229',
        max_tokens: 1000,
        messages: [
            {
                role: 'user',
                content: `Context: ${context}\n\nQuestion: ${question}\n\nPlease answer the question based on the given context.`
            }
        ]
    });

    return message.content[0].text;
}

async function searchAndAskClaude(query) {
    try {
        // Execute hybrid search
        const searchResults = await hybridSearch(query);

        // Prepare context
        const context = searchResults.map(result => result.payload.text).join('\n\n');

        // Ask Claude
        const answer = await askClaude(context, query);

        return answer;
    } catch (error) {
        console.error("There was an error:", error);
        return "Sorry there was an error.";
    }
}

// Usage example
async function main() {
    const query = "Example question?";
    const response = await searchAndAskClaude(query);
    console.log("Claude answer:", response);
}

main();

[davide445]

So far seems ollama (supporting bge-m3) it's not able to get out his sparse vectors, Qdrant own fastembed didn't support bge-m3 so far, I hope llama.cpp is able to extract them.

[davide445]

Langchain has already the classes to manage sparse embeddings and hybrid search https://api.python.langchain.com/en/latest/qdrant_api_reference.html Next another example code using langchain

const { QdrantClient } = require("@qdrant/qdrant-js");
const { SparseEmbeddings } = require("langchain-qdrant/sparse_embeddings");
const { BGEM3Embeddings } = require("langchain/embeddings/bge_m3");
const { QdrantVectorStore } = require("langchain/vectorstores/qdrant");

class BGEM3SparseEmbeddings extends SparseEmbeddings {
  constructor(config = {}) {
    super();
    this.embeddings = new BGEM3Embeddings(config);
  }

  async embedDocuments(texts) {
    const embeddings = await this.embeddings.embedDocuments(texts);
    return embeddings.map(embedding => ({
      indices: embedding.indices,
      values: embedding.values
    }));
  }

  async embedQuery(text) {
    const embedding = await this.embeddings.embedQuery(text);
    return {
      indices: embedding.indices,
      values: embedding.values
    };
  }
}

async function main() {
  const denseEmbedder = new BGEM3Embeddings();
  const sparseEmbedder = new BGEM3SparseEmbeddings();

  const qdrant = new QdrantClient({ url: "http://localhost:6333" });

  // Create a collection for hybrid embeddings
  await qdrant.createCollection("hybrid_collection", {
    vectors: {
      dense: {
        size: 1024, 
        distance: "Cosine",
      },
      sparse: {
        index: {
          on_disk: true,
        },
      },
    },
  });

  const docs = [
    "First document",
    "Second document",
    "Third document"
  ];

  const denseEmbeddings = await denseEmbedder.embedDocuments(docs);
  const sparseEmbeddings = await sparseEmbedder.embedDocuments(docs);

  // Insert documents with both embedding types
  for (let i = 0; i < docs.length; i++) {
    await qdrant.upsert("hybrid_collection", {
      wait: true,
      points: [
        {
          id: i.toString(),
          vector: {
            dense: denseEmbeddings[i],
            sparse: sparseEmbeddings[i],
          },
          payload: { text: docs[i] },
        },
      ],
    });
  }

  // Create QdrantVectorStore instance
  const vectorStore = await QdrantVectorStore.fromExistingCollection(
    denseEmbedder,
    {
      client: qdrant,
      collectionName: "hybrid_collection",
    }
  );

  // Execute hybrid search
  const query = "Query sample";
  const denseQueryEmbedding = await denseEmbedder.embedQuery(query);
  const sparseQueryEmbedding = await sparseEmbedder.embedQuery(query);

  const searchResult = await qdrant.search("hybrid_collection", {
    vector: {
      dense: denseQueryEmbedding,
      sparse: sparseQueryEmbedding,
    },
    limit: 5,
  });

  console.log("Hybrid search results:", searchResult);

  // Use LangChain for similar search (only dense embeddings)
  const langchainResults = await vectorStore.similaritySearch(query, 5);
  console.log("LangChain results:", langchainResults);
}

main().catch(console.error);

[davide445]

https://qdrant.tech/documentation/concepts/hybrid-queries/#hybrid-search