The old Enterprise Manager database control is replaced by Enterprise Manager database express in Oracle 12c.
It contains only basic administration capabilities as the advanced ones are included in Enterprise Manager cloud control
With EM database Express you can manage Security (Users, roles, profiles), Configuration (Instance Parameters, memory, database features), Storage (tablespaces, undo, redo, archive logs, control files), Performance.
Enterprise Manager needs the XML DB component.
You can configure the port used by EM database Express using : exec DBMS_XDB_CONFIG.setHTTPsPort(5500);
You can get the port configured for EM database Express using : select DBMS_XDB_CONFIG.getHTTPsPort from dual;
The EM_EXPRESS_BASIC (read-only role) and EM_EXPRESS_ALL (access all functionnalities) roles can be used to grant access to EM Database Express to non-administrative users.
You can’t start or stop your DB with EM database express, this means that you database is accessible through EM database express only when you opened it.
Listener should be up and running for access to EM Express being possible.
Alternative for performing some DBA admin tasks is the DBA tab of SQLDeveloper
