Please see this forum post https://forums.oracle.com/ords/apexds/post/how-can-i-convert-a-blob-to-base64-7597

Lisa, If you save the reports under shared folders other than custom by getting an admin role, those reports can not be preserved during upgrades and will be over written. the only folder that is preserved during upgrades is the custom folder under shared. Hope this helps. Venu

Hi Lisa, You should be able to save the reports/analysis in Customer folder under shared. That's the only folder that users can save reports to other than My Folder. Thanks Venu