What are "configuration files" in a DBMS?

Configuration files in a DBMS are text files holding settings that control how the database server runs.

They set parameters like:

• the connection port,
• paths to data files,
• the amount of memory used,
• the logging level,
• security and user settings.

Examples:

• In PostgreSQL, the postgresql.conf file (main parameters) and pg_hba.conf (access rights).
• In MySQL, the my.cnf or my.ini file.

Through configuration files, an administrator can, for example:

• change the maximum number of connections,
• configure backups,
• improve server performance.

So configuration files are the "brain" of the DBMS, holding all of its internal settings.