|Jira Agile 6.3
When a user tries to add an issue to an epic using the new Epic Link field, the following error message appears in the issue screen:
Screenshot of the problem at hand:
So far, this problem has only been detected to occur in JIRA Agile 6.2.2 or in later versions when using the SOAP UpdateIssue method. This is essentially caused by the issue key being a substring of another issue. For example ABC-12 is a substring of ABC-123.
As we can see from the Screenshot above, JIRA Agile seems to have truncated the Epic Name, and only used the prefix of the epic name for validation when searching for the epic. For example, lets say we have two epics with name "ABC-123 Testing Epic" and "ABC-12 Another Test". When we try to add an issue to the epic "ABC-123 Testing Epic", JIRA would only take the prefix of the epic name, in this case "ABC-123", and show the error "Epic with name 'ABC-123' is not unique.".
If you encounter this error, you may be able to run the following SQL Query and check for duplicate IDs or pkey values on each of the Epic issues returned in this query.