database files Definition

Files that contain project compilation data which are generated by the Quartus^® Prime software. Database files are created, used internally, and updated by the software during compilation, simulation, and other processes. You can recreate database files by recompiling or resimulating. The following are database file types:

Compiler Database File (.cdb)
Hierarchy Database File (.hdb)
Report Database File (.rdb)
Timing Database File (.tdb)

Note:

A Compiler Netlist File (.cnf) is another type of database file, and is either a Compiler Database File with the file name <revision name>.cnf.cdb or an Hierarchy Database File with the file name <revision names>.cnf.hdb.