I have a non-spatial table in Postgres and I would like to publish it as registered to Arcgis Server, is this possible?
I don't believe it is possible to publish any sort of table as a service to ArcGIS server directly. If you have both a feature class and a table in ArcMap/ArcGIS Pro and publish the whole map as a service, the table will be included, but I have never seen a method to publish just a table on its own.
If you have a hosting server, you can publish a hosted table to ArcGIS Enterprise, but this is a slightly different workflow: Share a table—ArcGIS Pro | Documentation
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