For buyers contracting authority
Reach for 48612000 when the data-storage engine is the thing being procured: a new database platform, a licence renewal for an existing one (Oracle, SQL Server and similar named products show up under this code), or the implementation and support that wraps a managed data layer.
The line that trips contracting authorities is the one against 48611000, Database software package. In practice the two overlap heavily, since a management system is delivered as a package; the working split is that 48611000 leans toward an off-the-shelf product purchase, while 48612000 covers the system as deployed and run. Where a contract bundles the licence with implementation and ongoing operation, 48612000 is the safer primary code.
Two more neighbours matter. If the deliverable is records-handling and document lifecycle rather than the raw data engine, that is electronic data management (48613000). If the system's job is to capture readings from instruments or sensors, that is data acquisition (48614000). Set the primary CPV code by the dominant purpose, not by the fact that a database sits somewhere in the stack.