Vector databáze — srovnání

Vector databases are a key technology for modern AI applications, similarity search, and RAG systems. In this article, we’ll compare the most popular solutions and help you choose the right one for your project.

What Are Vector Databases and Why Do We Need Them¶

Vector databases have become an indispensable tool for modern AI applications, especially in the context of LLMs and Retrieval-Augmented Generation (RAG). Unlike traditional relational databases that store structured data, vector databases specialize in storing and searching high-dimensional vectors — numerical representations of data like text, images, or audio.

The main advantage of vector databases is their ability to perform similarity search using cosine similarity, euclidean distance, or dot product. This enables finding semantically similar content even without exact matches, which is crucial for AI applications.

Pinecone: Managed Cloud Solution¶

Pinecone is a fully managed vector database built for production workloads. It offers high availability, automatic scaling, and optimized indexes for fast search.

Key Features¶

• Managed service with automatic scaling
• Real-time updates and metadata filtering
• Support for sparse and dense vectors
• Built-in monitoring and analytics

Basic Usage¶

import pinecone
from pinecone import Pinecone, ServerlessSpec

# Initialization
pc = Pinecone(api_key="your-api-key")

# Create index
pc.create_index(
    name="example-index",
    dimension=1536,
    metric="cosine",
    spec=ServerlessSpec(
        cloud='aws',
        region='us-east-1'
    )
)

# Connect to index
index = pc.Index("example-index")

# Insert vectors
vectors = [
    {
        "id": "doc1",
        "values": [0.1, 0.2, 0.3, ...],  # 1536 dimensions
        "metadata": {"title": "AI Article", "category": "tech"}
    }
]
index.upsert(vectors=vectors)

# Search
results = index.query(
    vector=[0.1, 0.15, 0.25, ...],
    top_k=5,
    include_metadata=True,
    filter={"category": "tech"}
)

Advantages and Disadvantages¶

Advantages: Zero infrastructure management, high availability, excellent documentation, optimized for production.

Disadvantages: Higher costs, vendor lock-in, free tier limitations.

ChromaDB: Open-source Simplicity¶

ChromaDB is an open-source vector database focused on ease of use and quick start. Ideal for prototyping and smaller applications, but scales to larger deployments.

Key Features¶

• Embedded and server mode
• Automatic embedding generation
• Support for multiple collections
• Python-first approach

Implementation¶

import chromadb
from chromadb.config import Settings

# Local embedded version
client = chromadb.Client()

# Or connect to server
# client = chromadb.HttpClient(host='localhost', port=8000)

# Create collection
collection = client.create_collection(
    name="documents",
    metadata={"description": "Document collection"}
)

# Add documents
collection.add(
    documents=["First document about AI", "Second article about ML"],
    metadatas=[
        {"source": "blog", "date": "2024-01-01"},
        {"source": "wiki", "date": "2024-01-02"}
    ],
    ids=["id1", "id2"]
)

# Search
results = collection.query(
    query_texts=["artificial intelligence"],
    n_results=2,
    where={"source": "blog"}
)

print(results['documents'])
print(results['distances'])

Advantages and Disadvantages¶

Advantages: Open-source, simple installation, automatic embeddings, active community.

Disadvantages: Limited scalability, fewer enterprise features, younger project.

Milvus: Enterprise Scalability¶

Milvus is a high-performance vector database designed for massive-scale deployments. It supports distributed architectures and is optimized for highest throughput.

Key Features¶

• Horizontal scaling
• GPU acceleration support
• Multiple index types (IVF, HNSW, ANNOY)
• Kubernetes native deployment

Working with Milvus¶

from pymilvus import connections, Collection, FieldSchema, CollectionSchema, DataType

# Connect
connections.connect("default", host="localhost", port="19530")

# Define schema
fields = [
    FieldSchema(name="id", dtype=DataType.INT64, is_primary=True, auto_id=True),
    FieldSchema(name="embedding", dtype=DataType.FLOAT_VECTOR, dim=1536),
    FieldSchema(name="text", dtype=DataType.VARCHAR, max_length=65535)
]
schema = CollectionSchema(fields, "Document embeddings")

# Create collection
collection = Collection("documents", schema)

# Create index
index_params = {
    "index_type": "HNSW",
    "metric_type": "COSINE",
    "params": {"M": 16, "efConstruction": 256}
}
collection.create_index("embedding", index_params)

# Insert data
entities = [
    [[0.1, 0.2, 0.3, ...], [0.4, 0.5, 0.6, ...]],  # embeddings
    ["First text", "Second text"]  # texts
]
collection.insert(entities)

# Load collection into memory
collection.load()

# Search
search_params = {"metric_type": "COSINE", "params": {"ef": 128}}
results = collection.search(
    [[0.1, 0.15, 0.25, ...]],  # query vector
    "embedding",
    search_params,
    limit=5,
    output_fields=["text"]
)

Advantages and Disadvantages¶

Advantages: Extreme scalability, high performance, flexible indexes, cloud-native.

Disadvantages: More complex setup, higher resource requirements, steeper learning curve.

Performance Comparison¶

When selecting a vector database, it’s important to consider performance characteristics for your specific use case:

• Latency: Pinecone typically <50ms, ChromaDB <100ms for smaller datasets, Milvus <10ms with optimal configuration
• Throughput: Milvus leads with thousands of QPS, Pinecone handles hundreds of QPS, ChromaDB tens of QPS
• Scalability: Milvus supports billions of vectors, Pinecone tens of millions per pod, ChromaDB millions in embedded mode

Cost and Deployment¶

Economic considerations are often the deciding factor:

• Pinecone: Pay-as-you-go model, approximately $70-400/month depending on usage
• ChromaDB: Open-source free, costs only for infrastructure
• Milvus: Open-source version free, managed Zilliz Cloud platform available

When to Use Which Database¶

Pinecone is ideal for teams wanting to quickly launch production-ready solutions without infrastructure worries. Great choice for startups and medium companies with clearly defined use cases.

ChromaDB I recommend for prototyping, MVPs, and applications with smaller data volumes. Excellent for experimenting and learning vector search concepts.

Milvus is the choice for enterprise deployments with high performance and scalability requirements. Ideal for companies with their own DevOps team and specific infrastructure requirements.

Summary¶

Vector database selection depends on your specific needs. Pinecone offers the simplest path to production with managed service, ChromaDB is great for rapid prototyping and smaller projects, while Milvus dominates the enterprise segment with highest scalability. I recommend starting with ChromaDB for experiments, moving to Pinecone for quick production deployment, and considering Milvus for high-scale applications with specific performance requirements.