pgvector
A PostgreSQL/Aurora extension that stores and searches embedding vectors.
pgvector is an open-source PostgreSQL extension that adds a native vector data type and similarity search operators (cosine, L2, inner product) directly to a relational database. Amazon Aurora PostgreSQL and Amazon RDS for PostgreSQL both support it, making either service usable as a vector store for retrieval-augmented generation (RAG) pipelines without provisioning a separate purpose-built vector database. The key exam distinction is that pgvector keeps vector search inside a familiar SQL engine alongside structured relational data, suiting workloads that already run on Aurora. Purpose-built vector databases such as Amazon OpenSearch Serverless or Amazon MemoryDB can offer higher throughput at very large scale, so the exam may test when pgvector is a practical trade-off versus a dedicated service.
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