Jonathan Katz: Vectors are the new JSON in PostgreSQL

Vectors are the new JSON. That in itself is an interesting statement, given vectors are a well-studied mathematical structure, and JSON is a data interchange format. And yet in the world of data storage and retrieval, both of these data representations have become the lingua franca of their domains and are either essential, or soon-to-be-essential, ingredients in modern application development. And if current trends continue (I think they will), vectors will be as crucial as JSON is for building applications. Generative AI and all the buzz around it has caused developers to look for convenient ways to store and run queries against the outputs of these systems, with PostgreSQL being a natural choice for a lot of reasons. But even with the hype around generative AI, this is not a new data pattern. Vectors, as a mathematical concept, have been around for hundreds of years. Machine learning has over a half-century worth of research. The array – the fundamental data structure for a vector – is taught in most introductory computer science classes. Even PostgreSQL has had support for vector operations for over 20 years (more on that later)! So, what is new? It’s the accessibility of these AI/ML algorithms and how easy it is to represent some “real world” structure (text, images, video) as a vector and store it for some future use by an application. And again, while folks may point to the fact it’s not new to store the output of these systems (“embeddings”) in data storage systems, the emergent pattern is the accessibility of being able to query and return this data in near real-time in almost any application. What does this have to do with PostgreSQL? Everything! Efficient storage and retrieval of a data type used in a common pattern greatly simplifies app development, lets people to keep their related ata in the same place, and can work with existing tooling. We saw this with JSON over 10 years ago, and now we’re seeing this with vector data. To understand why vectors are the new JSON, let’s rewi[...]