Database Systems
A database is an organized collection of data stored electronically. Database Management Systems (DBMS) provide interfaces for creating, querying, and managing databases.
Types of Databases
Relational databases (SQL) store data in tables with predefined schemas. Examples include PostgreSQL, MySQL, and SQLite. NoSQL databases include document stores (MongoDB), key-value stores (Redis), graph databases (Neo4j), and column stores (Cassandra).
Graph Databases
Neo4j is the leading graph database, using nodes, relationships, and properties to represent and store data. Cypher is Neo4j's query language. Graph databases excel at managing highly connected data, such as social networks, recommendation engines, and knowledge graphs.
Vector Databases
Vector databases like Pinecone are designed to store and search high-dimensional embeddings. They enable semantic search and are crucial components of RAG (Retrieval-Augmented Generation) systems. A RAG system retrieves relevant documents from a vector database and passes them to an LLM for answer generation.