For readability in code, we have started creating DB Links that use the following naming standard:
"{Account Name or Abbrev used by the link}@{Instance Connecting to}"
so we create a DB Link name like "MLA_NET@UKXXX069" and Oracle interestingly injects ".WORLD" just before the "@" in the name so we get "MLA_NET.WORLD@UKXXX069" stored in Oracle. As I am sure you know the ".WORLD" is not needed when using a DB Link, so our code does not include it. I was just looking to find our dependencies on a specific link and discovered the Used By tab for DB Links seems to assume the ".WORLD" is always at the end of the link.
As you can see here, I have 7 different DB Links that use the MLA_NET account, but connect to different Instances:
I found the Used By returned the same result set for all 7 DB Links, so I turned on Spool SQL to see how Toad populates Used By and attached is the Spool file.
Debug.SQL (2.9 KB)
When looking for Views or Materialized Views Toad was scanning for '@MLA_NET' and should be looking for '@MLA_NET.WORLD@UKXXX069' if someone included the '.WORLD' or '@MLA_NET@UKXXX069' if they excluded the '.WORLD' as both are valid in Oracle.
I assume very few people use a similar naming strategy for DB Links so this is probably impacting a very small number of users, it should probably be given a low priority.
If you have any questions. please let me know...