is there any possibility to access the data in relational datastore through arccatalog ? if yes does it shows spatial data or only tables ?as per the documentation esri says it does have tables in postgres relational datastore.
kindly suggest on this.
The ArcGIS Data Store is only supposed to be accessible via the REST interfaces (via the Hosting Server) and certainly if you want to 'support'. The PostgreSQL database uses none-standard ports, and hidden credentials to dissuade you from doing so.
If you want to use the data in a desktop product (recommend Pro) then connect via the REST endpoint or extract the data as a copy (fGDB) and use it that way. :)
Accessing the postgres database directly is not recommended by Esri however if you are really determine to access the relational db, I don't see what can stop you :).
Have you tried updating pg_hba.conf(back this up first) to trust all host? that way you can log in without requiring a password.