You can have more than one database in a PostgreSQL database cluster. You can create and authorize one geodatabase in each database.
The following graphic illustrates that there are two separate databases in one PostgreSQL database cluster and that each database contains a complete geodatabase:
The databases can have any unique name that follows PostgreSQL rules for identifiers, does not start with a number, and must use lowercase characters only.
You can use the Create Enterprise Geodatabase geoprocessing tool or a Python script to create additional databases and geodatabases on the PostgreSQL database cluster. Since you already designated the sde user when you created the first geodatabase, be sure to use the same password for the sde user when you run the tool a second time.
Each connection you make from ArcGIS to a geodatabase accesses only one database. For example, when you connect to database1 from ArcMap, you cannot query information from database2 through that same connection. To access the data in database2, set up a second database connection from ArcMap to it.