Hi,

If you specify db_filter or db_name in the odoo configuration file, then you will get only filtered databases.

Suppose if you set a db filter, then db's matching given filter will be listed and if you specify db_name in conf file, only that database will be shown.

Also if you are running via service file or command line, make sure you didn't pass db name in -d 

Thanks

You only need this min configuration to run ODOO.

db_host = localhost
db_port = 5432
db_password = postgres
db_user = odoo
xmlrpc_port = 8013
debug_mode = False
;data_dir=/home/dell/.local/share/Odoo/filestore
addons_path = /opt/odoo/addons

make sure you needed db_template, db_name, db_filter.
You don't need to specify db_filter if you need full list of dbs