Neo Technology, a startup with a commercial distribution of the Neo4j open-source graph database for storing and serving up information for applications, has brought on $20 million in new venture funding.

Graph databases are one flavor of non-relational database technology, which generally differs from the relational technology in place at big companies for decades. NoSQL databases have gotten plenty of venture backing lately. But unlike, say, key value stores or document databases, graph databases depict the relationships connecting various entities. For instance, a social network has good reason to determine how two people are related and which friends they have in common. Indeed, Facebook employs a graph database called Apache Giraph.

But Neo’s open-source database, and the commercially available version sporting business-friendly features, are being implemented for some serious purposes, Emil Eifrem, chief executive and a cofounder of Neo, told VentureBeat in an interview.

The technology is useful to e-commerce sites for making recommendations, or to graph-based search engines like Crunchbase. Telecommunications companies use it to figure out what might happen if one piece of networking infrastructure goes down. And it even plays a role in complex domains of identity and access management, and master data management, Eifrem said.

Eifrem said Neo now has 150-200 subscription customers. Think Accenture, eBay, HP, National Geographic, and Walmart. That’s not too shabby for a startup pushing a technology that isn’t as well understood as the relational databases from companies like IBM and Oracle, which Eifrem said are his company’s most visible competitors.

But Eifrem believes big companies actually are starting to understand graph databases. He pointed to technology analysis firm Forrester, which found that more than one quarter of enterprises would use graph databases by 2017.

“A lot of smart people think there’s a lot of value in this market,” Eifrem said.

Meanwhile, other startups packing graph capability can benefit from an increase in adoption. Consider Dato (formerly GraphLab) and Orchestrate, for instance.

About 80 people now work for Neo, Eifrem said.

Creandum led the new funding round, while Conor Venture Partners, Dawn Capital, Fidelity Growth Partners Europe, and Sunstone Capital also participated.

To date, San Mateo, Calif.-based Neo Technology has raised approximately $45 million.