title: on using oracle database link theres an error "ORA-12154 TNS Could not resolve the connect identifier specified"
body: <p>I'm trying to define a database link on oracle 10.2 with connection identifier that throws the error in the question header.
  I have the connection identifier (service name) in my tnsnames.ora file.
  I can connect with sqlplus using this service name. no problem.
  This is the creation sql:</p>
  
  <p>create database link dev1.REGRESS.RDBMS.DEV.US.ORACLE.COM
    connect to user1 identified by pass1
    using 'dev1';</p>
  
  <p>select using the link:
  select * from t_users@dev1;</p>
  
  <p>I get: ORA-12154: TNS:could not resolve the connect identifier specified</p>
  
  <p>connecting to oracle with sqlplus to the 'unidentified' service (with no problem):
  sqlplus user1/pass1@dev1</p>
  
  <p>I defined another link to the same database I'm woking in (loopback) - works OK.</p>
  
  <p>I read and tried anything I could find about the subject but did not solve this.</p>
  
  <p>Any suggestions?</p>