Problem
The actual value of a custom field from an Issue should be selected
Solution
select CAST(pk.PROJECT_KEY as VARCHAR(10))+'-'+CAST(issue.issuenum AS varchar(10)), cfo.customvalue FROM CustomFieldValue cfv INNER JOIN CustomField CF on CF.Id = CFV.CustomField INNER JOIN CustomFieldOption CFO on CF.Id = CFO.CustomField INNER JOIN jiraissue issue on issue.id = cfv.issue INNER JOIN project_key pk on PROJECT_ID=issue.PROJECT WHERE cf.CFName = 'Classification' And CAST(CFO.Id AS VARCHAR(10)) =CFV.StringValue;