Oracle Database 12c: EM Express
Oracle Enterprise Manager Database Express,
also referred to as EM
Express, is a database management tool that
focuses primarily on performance management and
monitoring. However, it does include
basic administration functions to assist the
When users first log into EM Express, they see
the home page which displays information about the
database, as well as performance data, such as
resource usage, average active sessions, and
monitored SQL statements.
Database Administration Functions
The three main categories of administrative
The four main features available in the Configuration
menu are Initialization Parameters, Memory Configuration,
Database Feature Usage and Database Properties.
Database Administrators can view and set initialization
parameters for one or more instances of the database.
They can also determine how memory has been configured,
and in particular, the amount of memory allocated to the
SGA and PGA, the top processes consuming memory, and
whether or not any of the automatic memory management
features are in use. In addition, memory advisor
data is also displayed on the page. To see an
example of the Memory page, click
As part of Storage administration, DBAs can manage redo
logs, archive logs, and tablespaces (view space
consumption, create and/or alter tablespaces). In
addition, DBAs are also given some visibility into the
control file contents. DBAs can also view the Undo
Advisor, as well as undo statistics, such as the undo
generation rate and undo space usage. To see an
example of the Undo Page, click
DBAs can use the features available in the Security menu
to manage users, roles and profiles by creating, altering
or granting and revoking privileges from them.
Frequently Asked Questions
- How can I see advisor data on the Memory
- I'm trying to perform a task that I used
to do in DB Control. Where is it in EM Express?
- Why do I see a "Warning" icon on the
How can I see Advisor Data on
the Memory Page?
The advisor data visible at the top right panel of the
Memory page is dependent on the memory configuration
settings that are in use.
- If Automatic Memory Management is used, then only the
Memory Advisor is displayed on the page.
- If Automatic Shared Memory Management is used, then
the SGA Advisor, along with the PGA Advisor is
- If Manual Shared Memory Management is used, then the
Buffer Cache Advisor, along with the PGA Advisor is
I'm trying to perform a task
that I used to do in DB Control. Where is it in EM
EM Express is not a direct replacement for DB Control.
As explained in the Architecture
section, EM Express is built inside the database server and
there are limitations as to what it can do. EM Express
is also focused on providing performance management and
monitoring functionality, and is not meant to be an all
around database administration tool.
Why do I see a "Warning" icon
on the Memory Page?
The warning icon is displayed if the memory configuration is
different across the instances in your RAC cluster.
For example, this may be displayed if one instance uses
Automatic Memory Management, while the other instance uses
Manual Shared Memory Management.