union ile yapamazsin
Yukaridaki cevapta da belirtildigi gibi
Union öperatörü, iki veya daha fazla Select durumlu sonuç kümesini birleştirmek için kullanılır


group by ve string aggregate yapman lazim


select issues."ID", issues."ISSUE_HEADER", issues."ISSUE_CONTENT", issues."ISSUE_IMAGE", issues."ISSUE_NO", issues."APPROVE_DATE", issues."NEWSPAPER_PUBLISH_DATE", issues."NEWSPAPER_PUBLISH_NO", issues."COMPOSITION", issues."VOLUME", issues."AUTHOR", issues."RELEASE_DATE", issues."INSERT_DATE",
--- string aggregate syntax ---
files.file_type & files.file_name as issue_files
--- string aggregate syntax ---
from issues
left join files on issues.id = files.issue_id
group by issues."ID", issues."ISSUE_HEADER", issues."ISSUE_CONTENT", issues."ISSUE_IMAGE", issues."ISSUE_NO", issues."APPROVE_DATE", issues."NEWSPAPER_PUBLISH_DATE", issues."NEWSPAPER_PUBLISH_NO", issues."COMPOSITION", issues."VOLUME", issues."AUTHOR", issues."RELEASE_DATE", issues."INSERT_DATE",