I have an ArcGIS Enterprise 10.5 environment with a SQL server Enterprise Geodatabase. Most of the users of Portal are Level 2 publishers or creators. There have been numerous apps and dashboards created using published, referenced feature layers using data from the SDE with no access issues until now.
With a recently created feature service and Dashboard I have a small group of level 1 viewers who cannot load the feature service in either the dashboard or a stand alone web map. They can see the feature service since it is shared to the group that they are in, but when a level one user attempts to load the feature layer in a web map they receive the error message saying the data could not be loaded into the map.
Here are the details about the layer. It is a SQL view of one spatial and one non-spatial table both in the same database. Neither of the tables are versioned. It is published to Portal using ArcMap 10.5 as referenced data. All level 2 users can access it and use the Dashboard that contains it. My thoughts are that it has something to do with permissions on the tables in the database, but I don't know exactly.