Qdrant 向量搜索
用於 RAG 和語義搜索的高性能向量相似度搜索引擎。在構建需要快速最近鄰搜索、帶過濾的混合搜索或具有 Rust 驅動性能的可擴展向量存儲的生產級 RAG 系統時使用。
技能元數據
| 來源 | 可選 — 使用 hermes skills install official/mlops/qdrant 安裝 |
| 路徑 | optional-skills/mlops/qdrant |
| 版本 | 1.0.0 |
| 作者 | Orchestra Research |
| 許可證 | MIT |
| 依賴項 | qdrant-client>=1.12.0 |
| 標籤 | RAG, Vector Search, Qdrant, Semantic Search, Embeddings, Similarity Search, HNSW, Production, Distributed |
參考:完整 SKILL.md
信息
以下是 Hermes 在觸發此技能時加載的完整技能定義。這是技能激活時代理看到的指令。
Qdrant - 向量相似度搜索引擎
用 Rust 編寫的高性能向量數據庫,適用於生產級 RAG 和語義搜索。
何時使用 Qdrant
在以下情況使用 Qdrant:
- 構建需要低延遲的生產級 RAG 系統
- 需要混合搜索(向量 + 元數據過濾)
- 需要通過分片/複製實現水平擴展
- 希望本地部署以完全控制數據
- 需要每條記錄的多向量存儲(稠密 + 稀疏)
- 構建實時推薦系統
主要特性:
- Rust 驅動:內存安全,高性能
- 豐富的過濾:在搜索期間按任意 payload 字段過濾
- 多向量支持:每個點支持稠密、稀疏、多稠密向量
- 量化:標量、乘積、二進制量化以提高內存效率
- 分佈式:Raft 共識、分片、複製
- REST + gRPC:兩種 API 具有完整的功能對等性
改用其他替代方案:
- Chroma:設置更簡單,適用於嵌入式用例
- FAISS:極致原始速度,適用於研究/批處理
- Pinecone:全託管,首選零運維
- Weaviate:偏好 GraphQL,內置向量化器
快速入門
安裝
# 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
Points - 基本數據單元
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
)
Collections - 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}")
距離度量
| 度量 | 用例 | 範圍 |
|---|---|---|
COSINE | 文本嵌入,歸一化向量 | 0 到 2 |
EUCLID | 空間數據,圖像特徵 | 0 到 ∞ |
DOT | 推薦,未歸一化 | -∞ 到 ∞ |
MANHATTAN | 稀疏特徵,離散數據 | 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)
)
過濾搜索
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
與 sentence-transformers 結合
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?"
與 LangChain 結合
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})
與 LlamaIndex 結合
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(內存優化)
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
)
Payload 索引
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
生產部署
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"
)
性能調優
# 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}
)
最佳實踐
- 批量操作 - 使用批量 upsert/search 以提高效率
- Payload 索引 - 對用於過濾的字段建立索引
- 量化 - 對大型集合(>100 萬向量)啟用
- 分片 - 對超過 1000 萬向量的集合使用
- 磁盤存儲 - 對大型 payload 啟用
on_disk_payload - 連接池 - 複用客戶端實例
常見問題
帶過濾的搜索緩慢:
# Create payload index for filtered fields
client.create_payload_index(
collection_name="docs",
field_name="category",
field_schema=PayloadSchemaType.KEYWORD
)
內存不足:
# 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
)
連接問題:
# Use timeout and retry
client = QdrantClient(
host="localhost",
port=6333,
timeout=30,
prefer_grpc=True # gRPC for better performance
)
參考資料
資源
- GitHub: https://github.com/qdrant/qdrant (22k+ stars)
- 文檔: https://qdrant.tech/documentation/
- Python 客戶端: https://github.com/qdrant/qdrant-client
- 雲服務: https://cloud.qdrant.io
- 版本: 1.12.0+
- 許可證: Apache 2.0