The phrase "a related database" is correct and usable in written English.
You can use it when referring to a database that has a connection or relevance to another subject or database.
Example: "To enhance our research, we need to access a related database that contains similar data sets."
Alternatives: "an associated database" or "a connected database".
My undergrad thesis; I also created a related database of spherical hypertree divisors generated using Macaulay2.
For indexing of articles covering the period 1929-1984, there is a related database, Art Retrospective.
For indexing, abstracting, and selected full-text coverage for the years 1984 to present, there is a related database, Art Full Text.
Each result produced with this access allows fetching more results from a related database in the query.
All data and comparative genomics concerning the H. pylori B38 genome are stored in PyloriScope http://www.genoscope.cns.fr/agc/mage, a related database that is available to the public.
A related database is Terpmed (http://www.terpmed.eu/databases.html) which contains information about plant terpenoids, natural products, and other secondary metabolites important for use as therapeutic drugs.
ClinVar is collecting DNA findings on as many people as possible; a separate but related database called ClinGen is trying to understand what those findings mean.
I have gathered the data from this study into an archive, currently housed at Duke, and I oversee the computerization of systematically collected daily data, incorporating this and related material into a relational database.
The software is composed of a set of 37 related database tables, with 118 relationships among them.
Expect Labs states that devs simply need to point the API at the related database to create a custom knowledge graph.
Protein sequences were derived from a related STRING database (http://string-db.org/).
