column, maintained by Roman Atachiants, is a “High-performance, columnar, in-memory store with bitmap indexing in Go”. Deciding how to store data in memory can be tricky, depending on requirements. Sometimes you don’t need a full Database, but want something more than just structs, slices, and maps.
Saltcorn lets you create web-based Database applications with a drag and drop interface. It’s open source (MIT-licensed, even) and written in JavaScript.
In Databases, EdgeDB sounds very interesting. Their beta announcement has information. It’s built upon PostgreSQL. It’s designed to improve upon and overcome the limitations of SQL, offering its own language that gets converted into SQL for PostgreSQL. Built-in support for schema migrations. Includes its own binary protocol that connects to Go, Python, NodeJS, but also has HTTP and GraphQL APIs.
This is a long article, but with good details on aspects of Databases that will likely trip people up. See: Things I wished more developers knew about databases. This article is mostly RDBMS-centric, but many of the concepts apply elsewhere.