title: “Qdrant Vector Search — High-performance vector similarity search engine for RAG and semantic search” sidebar_label: “Qdrant Vector Search” description: “High-performance vector similarity search engine for RAG and semantic search”
{/* 本页面由 website/scripts/generate-skill-docs.py 根据技能对应的 SKILL.md 文件自动生成。请直接编辑源文件 SKILL.md,而非此页面。 */}
Qdrant 向量搜索引擎
专为 RAG 和语义搜索设计的高性能向量相似度搜索引擎。适用于构建需要快速最近邻搜索、混合搜索(向量与元数据过滤结合)或具备 Rust 强大性能支持的可扩展向量存储的实战级 RAG 系统。
技能元数据
| 来源 | 可选 — 通过 hermes skills install official/mlops/qdrant 安装 |
| 路径 | optional-skills/mlops/qdrant |
| 版本 | 1.0.0 |
| 开发者 | Orchestra Research |
| 许可证 | MIT |
| 依赖项 | qdrant-client>=1.12.0 |
| 支持平台 | linux、macos、windows |
| 标签 | RAG、向量搜索、Qdrant、语义搜索、嵌入向量、相似度搜索、HNSW、生产环境、分布式 |
参考:完整 SKILL.md 内容
Qdrant —— 向量相似度搜索引擎
基于 Rust 开发的高性能向量数据库,专为实战级 RAG 和语义搜索而设计。
何时使用 Qdrant
以下场景适合使用 Qdrant:
- 构建对低延迟有较高要求的实战级 RAG 系统
- 需要混合搜索功能(向量数据与元数据过滤结合)
- 需要通过分片/复制实现水平扩展
- 希望在本地部署以实现对数据的完全控制
- 每条记录需要存储多种向量格式(密集向量、稀疏向量)
- 开发实时推荐系统
核心特性:
- Rust 强力驱动:具备内存安全性与高性能
- 丰富过滤功能:搜索时可按任意字段进行过滤
- 多类型向量支持:单条数据可存储密集向量、稀疏向量及多种密集向量格式
- 量化技术:提供标量量化、乘积量化、二进制量化等多种方式以优化内存使用
- 分布式架构:支持 Raft 共识机制、分片与复制功能
- REST + gRPC 双接口:两种 API 具备完全一致的功能特性
可选替代方案:
- Chroma:部署更简单,适用于嵌入式场景
- FAISS:原始处理速度最快,适合研究用途及批量处理
- Pinecone:全托管服务,适合无需自行运维的场景
- Weaviate:优先支持 GraphQL 接口,内置向量化工具
快速入门
安装
# Python client
pip install qdrant-client
# Docker (recommended for development)
docker run -p 6333:6333 -p 6334:6334 qdrant/qdrant
# Docker with persistent storage
docker run -p 6333:6333 -p 6334:6334 \
-v $(pwd)/qdrant_storage:/qdrant/storage \
qdrant/qdrant
基本用法
from qdrant_client import QdrantClient
from qdrant_client.models import Distance, VectorParams, PointStruct
# Connect to Qdrant
client = QdrantClient(host="localhost", port=6333)
# Create collection
client.create_collection(
collection_name="documents",
vectors_config=VectorParams(size=384, distance=Distance.COSINE)
)
# Insert vectors with payload
client.upsert(
collection_name="documents",
points=[
PointStruct(
id=1,
vector=[0.1, 0.2, ...], # 384-dim vector
payload={"title": "Doc 1", "category": "tech"}
),
PointStruct(
id=2,
vector=[0.3, 0.4, ...],
payload={"title": "Doc 2", "category": "science"}
)
]
)
# Search with filtering
results = client.search(
collection_name="documents",
query_vector=[0.15, 0.25, ...],
query_filter={
"must": [{"key": "category", "match": {"value": "tech"}}]
},
limit=10
)
for point in results:
print(f"ID: {point.id}, Score: {point.score}, Payload: {point.payload}")
核心概念
积分——基本数据单位
from qdrant_client.models import PointStruct
# Point = ID + Vector(s) + Payload
point = PointStruct(
id=123, # Integer or UUID string
vector=[0.1, 0.2, 0.3, ...], # Dense vector
payload={ # Arbitrary JSON metadata
"title": "Document title",
"category": "tech",
"timestamp": 1699900000,
"tags": ["python", "ml"]
}
)
# Batch upsert (recommended)
client.upsert(
collection_name="documents",
points=[point1, point2, point3],
wait=True # Wait for indexing
)
集合——向量容器
from qdrant_client.models import VectorParams, Distance, HnswConfigDiff
# Create with HNSW configuration
client.create_collection(
collection_name="documents",
vectors_config=VectorParams(
size=384, # Vector dimensions
distance=Distance.COSINE # COSINE, EUCLID, DOT, MANHATTAN
),
hnsw_config=HnswConfigDiff(
m=16, # Connections per node (default 16)
ef_construct=100, # Build-time accuracy (default 100)
full_scan_threshold=10000 # Switch to brute force below this
),
on_disk_payload=True # Store payload on disk
)
# Collection info
info = client.get_collection("documents")
print(f"Points: {info.points_count}, Vectors: {info.vectors_count}")
距离度量标准
| 度量标准 | 使用场景 | 取值范围 |
|---|---|---|
COSINE | 文本嵌入、标准化向量 | 0 到 2 |
EUCLID | 空间数据、图像特征 | 0 到 ∞ |
DOT | 推荐系统、未标准化数据 | -∞ 到 ∞ |
MANHATTAN | 稀疏特征、离散数据 | 0 到 ∞ |
搜索操作
基本搜索
# Simple nearest neighbor search
results = client.search(
collection_name="documents",
query_vector=[0.1, 0.2, ...],
limit=10,
with_payload=True,
with_vectors=False # Don't return vectors (faster)
)
筛选搜索
from qdrant_client.models import Filter, FieldCondition, MatchValue, Range
# Complex filtering
results = client.search(
collection_name="documents",
query_vector=query_embedding,
query_filter=Filter(
must=[
FieldCondition(key="category", match=MatchValue(value="tech")),
FieldCondition(key="timestamp", range=Range(gte=1699000000))
],
must_not=[
FieldCondition(key="status", match=MatchValue(value="archived"))
]
),
limit=10
)
# Shorthand filter syntax
results = client.search(
collection_name="documents",
query_vector=query_embedding,
query_filter={
"must": [
{"key": "category", "match": {"value": "tech"}},
{"key": "price", "range": {"gte": 10, "lte": 100}}
]
},
limit=10
)
批量搜索
from qdrant_client.models import SearchRequest
# Multiple queries in one request
results = client.search_batch(
collection_name="documents",
requests=[
SearchRequest(vector=[0.1, ...], limit=5),
SearchRequest(vector=[0.2, ...], limit=5, filter={"must": [...]}),
SearchRequest(vector=[0.3, ...], limit=10)
]
)
RAG集成
使用sentence-transformers实现
from sentence_transformers import SentenceTransformer
from qdrant_client import QdrantClient
from qdrant_client.models import VectorParams, Distance, PointStruct
# Initialize
encoder = SentenceTransformer("all-MiniLM-L6-v2")
client = QdrantClient(host="localhost", port=6333)
# Create collection
client.create_collection(
collection_name="knowledge_base",
vectors_config=VectorParams(size=384, distance=Distance.COSINE)
)
# Index documents
documents = [
{"id": 1, "text": "Python is a programming language", "source": "wiki"},
{"id": 2, "text": "Machine learning uses algorithms", "source": "textbook"},
]
points = [
PointStruct(
id=doc["id"],
vector=encoder.encode(doc["text"]).tolist(),
payload={"text": doc["text"], "source": doc["source"]}
)
for doc in documents
]
client.upsert(collection_name="knowledge_base", points=points)
# RAG retrieval
def retrieve(query: str, top_k: int = 5) -> list[dict]:
query_vector = encoder.encode(query).tolist()
results = client.search(
collection_name="knowledge_base",
query_vector=query_vector,
limit=top_k
)
return [{"text": r.payload["text"], "score": r.score} for r in results]
# Use in RAG pipeline
context = retrieve("What is Python?")
prompt = f"Context: {context}\n\nQuestion: What is Python?"
集成 LangChain 使用
from langchain_community.vectorstores import Qdrant
from langchain_community.embeddings import HuggingFaceEmbeddings
embeddings = HuggingFaceEmbeddings(model_name="all-MiniLM-L6-v2")
vectorstore = Qdrant.from_documents(documents, embeddings, url="http://localhost:6333", collection_name="docs")
retriever = vectorstore.as_retriever(search_kwargs={"k": 5})
集成 LlamaIndex 使用
from llama_index.vector_stores.qdrant import QdrantVectorStore
from llama_index.core import VectorStoreIndex, StorageContext
vector_store = QdrantVectorStore(client=client, collection_name="llama_docs")
storage_context = StorageContext.from_defaults(vector_store=vector_store)
index = VectorStoreIndex.from_documents(documents, storage_context=storage_context)
query_engine = index.as_query_engine()
多向量支持
命名向量(不同的嵌入模型)
from qdrant_client.models import VectorParams, Distance
# Collection with multiple vector types
client.create_collection(
collection_name="hybrid_search",
vectors_config={
"dense": VectorParams(size=384, distance=Distance.COSINE),
"sparse": VectorParams(size=30000, distance=Distance.DOT)
}
)
# Insert with named vectors
client.upsert(
collection_name="hybrid_search",
points=[
PointStruct(
id=1,
vector={
"dense": dense_embedding,
"sparse": sparse_embedding
},
payload={"text": "document text"}
)
]
)
# Search specific vector
results = client.search(
collection_name="hybrid_search",
query_vector=("dense", query_dense), # Specify which vector
limit=10
)
稀疏向量(BM25、SPLADE)
from qdrant_client.models import SparseVectorParams, SparseIndexParams, SparseVector
# Collection with sparse vectors
client.create_collection(
collection_name="sparse_search",
vectors_config={},
sparse_vectors_config={"text": SparseVectorParams(index=SparseIndexParams(on_disk=False))}
)
# Insert sparse vector
client.upsert(
collection_name="sparse_search",
points=[PointStruct(id=1, vector={"text": SparseVector(indices=[1, 5, 100], values=[0.5, 0.8, 0.2])}, payload={"text": "document"})]
)
量化(内存优化)
from qdrant_client.models import ScalarQuantization, ScalarQuantizationConfig, ScalarType
# Scalar quantization (4x memory reduction)
client.create_collection(
collection_name="quantized",
vectors_config=VectorParams(size=384, distance=Distance.COSINE),
quantization_config=ScalarQuantization(
scalar=ScalarQuantizationConfig(
type=ScalarType.INT8,
quantile=0.99, # Clip outliers
always_ram=True # Keep quantized in RAM
)
)
)
# Search with rescoring
results = client.search(
collection_name="quantized",
query_vector=query,
search_params={"quantization": {"rescore": True}}, # Rescore top results
limit=10
)
载荷索引功能
from qdrant_client.models import PayloadSchemaType
# Create payload index for faster filtering
client.create_payload_index(
collection_name="documents",
field_name="category",
field_schema=PayloadSchemaType.KEYWORD
)
client.create_payload_index(
collection_name="documents",
field_name="timestamp",
field_schema=PayloadSchemaType.INTEGER
)
# Index types: KEYWORD, INTEGER, FLOAT, GEO, TEXT (full-text), BOOL
生产环境部署
Qdrant Cloud
from qdrant_client import QdrantClient
# Connect to Qdrant Cloud
client = QdrantClient(
url="https://your-cluster.cloud.qdrant.io",
api_key="your-api-key"
)
性能调优
# Optimize for search speed (higher recall)
client.update_collection(
collection_name="documents",
hnsw_config=HnswConfigDiff(ef_construct=200, m=32)
)
# Optimize for indexing speed (bulk loads)
client.update_collection(
collection_name="documents",
optimizer_config={"indexing_threshold": 20000}
)
最佳实践
- 批量操作——使用批量插入/查询以提高效率
- 负载索引——对过滤条件中用到的字段进行索引
- 量化处理——对于包含超过100万个向量的大型集合,建议启用该功能
- 分片——当集合中的向量数量超过1000万时,应采用分片机制
- 磁盘存储——对于较大的负载数据,建议启用
on_disk_payload选项 - 连接池——重复使用客户端实例
常见问题
带过滤条件的查询速度缓慢:
# Create payload index for filtered fields
client.create_payload_index(
collection_name="docs",
field_name="category",
field_schema=PayloadSchemaType.KEYWORD
)
内存不足:
# Enable quantization and on-disk storage
client.create_collection(
collection_name="large_collection",
vectors_config=VectorParams(size=384, distance=Distance.COSINE),
quantization_config=ScalarQuantization(...),
on_disk_payload=True
)
连接问题:
# Use timeout and retry
client = QdrantClient(
host="localhost",
port=6333,
timeout=30,
prefer_grpc=True # gRPC for better performance
)
参考资料
资源链接
- GitHub仓库:https://github.com/qdrant/qdrant(拥有2.2万+星标)
- 官方文档:https://qdrant.tech/documentation/
- Python客户端:https://github.com/qdrant/qdrant-client
- 云服务平台:https://cloud.qdrant.io
- 当前版本:1.12.0及以上
- 许可证:Apache 2.0