Melli Annamalai has led graph technology product management at Oracle for the second half of her 27 years there, after a NASA-funded PhD in satellite image retrieval, early semantic web work, medical imaging search, and Hadoop-era big data.
She joins Vivek Khandelwal and Joshua Thomas to make an unusually candid case against overselling knowledge graphs, and to explain the converged-database approach Oracle is betting on instead of moving data into a separate graph layer.
They talk through why RDF and SPARQL never won broad enterprise adoption despite decades of investment, why she still says she hopes the current AI-driven wave of interest doesn't fail, what actually separates an ontology from a comment or annotation, how to start building an ontology without the year and a half of upfront investment the old approach demanded, and what Oracle means when it says agents, property graphs, and vector search all run inside one SQL-addressable database.
Key takeaways:
- Semantic web technology stalled the first time around because it needed its own tooling ecosystem, its own query language (SPARQL), and a learning curve senior management wouldn't sign up for. SQL just kept working.
- Melli's own hedge on the current AI-driven knowledge graph wave: "I hope it doesn't fail." The line between what an LLM can do, what vector search can do, and what a graph is actually needed for is still not clearly drawn.
- An ontology, in her definition, is a schema for your data: a precise description of what things are and how they relate, more shareable and less ambiguous than a text annotation.
- Projects fail most often from over-engineering (converting everything into a knowledge graph instead of keeping relational data relational), immature tooling, and a security team that vetoes an unfamiliar vendor after the work is already done.
- Oracle's pitch is convergence: property graphs, RDF/SPARQL wrapped in SQL, vector search, and PL/SQL-defined AI agents all run inside one database, so the same data doesn't have to move to a different system to be queried a different way.