Steve Jones explains schema types:
OLTP/Relational
The type of schema that many of us work with is the standard OLTP or relational model. We have lots of transaction tables, most should have a PK, some of which have PKs. The schema expands to meet different needs and can have lots of entities.
It may just be the time of morning but “Galaxy schema” sounds dumb specifically because the Kimball style of star schema implicitly includes what the galaxy schema shows. Dimensions are conformed, which means they apply across facts, which implies that there may be multiple facts in the schema design. This means that galaxy schemas necessarily star schemas. For the sake of education, we tend to focus on one fact table but a star schema with two fact tables is still a star schema.
Anyhow, that’s my minor rant of the day. It’s not Steve’s fault somebody misunderstood the concept of star schemas and began promulgating this unnecessary term.