Effective with ArcGIS 10.4, you can read and write to PostGIS geometry in supported PostgreSQL databases without need for any additional extensions. I've only used an Advanced license for this, but I believe a Standard license can also connect to a non-geodatabase PG server database and use that workspace as a destination for vector creation tools. It's more cumbersome, but you can also use Basic license clients to write to tables using SQL with Python (via arcpy.ArcSDESQLExecute). Read-only Query Layers have been an option with all licemse levels since ArcGIS 10.0.

Effective with ArcGIS 10.4, you can read and write to PostGIS geometry in supported PostgreSQL databases without need for any additional extensions. I've only used an Advanced license for this, but I believe a Standard license can also connect to a non-geodatabase PG server database and use that workspace as a destination for vector creation tools. It's more cumbersome, but you can also use Basic license clients to write to tables using SQL with Python (via arcpy.ArcSDESQLExecute). Read-only Query Layers have been an option with all license levels since ArcGIS 10.0.

Effective with ArcGIS 10.4, you can read and write to PostGIS geometry in supported PostgreSQL databases without need for any additional externsions. I've only used an Advanced license for this, but I believe a Standard license can also connect to a non-geodatabase PG server database and use that workspace as a destination for vector creation tools. It's more cumbersome, but you can also use Basic license clients to write to tables using SQL with Python (via arcpy.ArcSDESQLExecute). Read-only Query Layers have been an option with all licemse levels since ArcGIS 10.0.

Effective with ArcGIS 10.4, you can read and write to PostGIS geometry in supported PostgreSQL databases without need for any additional extensions. I've only used an Advanced license for this, but I believe a Standard license can also connect to a non-geodatabase PG server database and use that workspace as a destination for vector creation tools. It's more cumbersome, but you can also use Basic license clients to write to tables using SQL with Python (via arcpy.ArcSDESQLExecute). Read-only Query Layers have been an option with all licemse levels since ArcGIS 10.0.