Hi, @Miriam Orzitzer Welcome to the Microsoft Q&A forum, Thanks for posting your question and using Azure services.
As we understand the ask here is you want to know how to use store procedures and functions written in java for the Azure PostgreSQL service.
Yes you are right unfortunately we do not support these extensions.I think this due to the natural of PaaS service and the capabilities of java extension itself.
Here are the supported extensions by Azure PostgreSQL
Please let me know if you need more information.
Regards
Geetha
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