Oracle service names with a minus sign (?) Are there any reasons not to use minus signs/dashes/hyphens in Oracle service names?
DBMS_SERVICE, tnsping and sqlplus seem to be fine, but the documentation says no. 

We are switching from Oracle SIDs to service names. Apparently, they can be longer than SIDs (64 chars instead of 8), and can contain a domain name (hence dots . and minus signs -). The documentation of DBMS_SERVICE says that service_name is limited to 64 characters, and network_name is limited to the NET service_name character set 
which is restricted to 

[a...z] [A...Z] [0...9] _ 


So, what about dots and hyphens? Are they ok or not?

http://docs.oracle.com/cd/E11882_01/appdev.112/e40758/d_serv.htm#ARPLS68018
http://docs.oracle.com/cd/E11882_01/network.112/e10835/syntax.htm#NETRF175
Oracle said no, only [a...z] [A...Z] [0...9] _