It is of fundamental importance to understand Oracle Database architecture. We have
discussed some of these topics in the previous modules. In this module, we will cover
these topics in details from the point of view of database administrators. To a student
beginning to learn Oracle database, it is difficult to visualize Oracle Database architecture
without GUI tools. We will use the GUI tools provided by Oracle, such as Oracle
Enterprise Manager Console, in our study. Students learn not only these powerful tools
but also the Oracle database architecture.
1. Introduction to Oracle Database
In this section, the discussion on Oracle Database architecture is divided into the
2. Database and instance.
3. Oracle network
4. Database storage, tablespaces and datafiles.
5. Schema and schema objects
6. Other database components.
II. Introduction to Oracle security.
This section focuses on management of Oracle database access through user
accounts and database privileges. The topics include establishment of user
accounts and manage system, schema object privileges and roles. It is also
covered how to grant or revoke a database privilege and to tune database access
III. Introduction of Oracle database dictionary views.
The data dictionary is key information resource used by Oracle itself and users as
well. The concept of data dictionary will be discussed. Students will learn how
to look up for information about an Oracle database.
IV. Learning GUI tool to view and manage database.
1. Oracle enterprise Manager Console.
2. Create a database after installation and configure Oracle Network.
References and review questions are listed.
At the conclusion of this module, the student will be able to:
• Understand Oracle database architecture.
• Understand Oracle database instance, memory structure, user and Oracle
• Understand Oracle network.
• Create tablespaces and manage database storage and schema objects.
• Understand basic Oracle security, user account, role, system and object
privileges. and create user account and grant or revock database privileges.
• Understand and use Oracle data dictionary views.
• Use Oracle Enterprise Manager Console.
I. Introduction to Oracle Database architecture.
Basic Oracle database architecture consists of database server and Oracle
network. Oracle database server provides database services to any Oracle
database clients. Oracle clients are all considered as remote database users. In
other words, Oracle clients connect to an Oracle database through a network, even
though the clients may be local. This is a typical distributed database system or
client-server environment, in which a task is shared between a server and a client.
We start with Oracle database server and then discuss Oracle network.
In recent years, Oracle has developed a set of GUI tools to help Oracle database
administrators (DBA) manage their databases. Oracle Enterprise Manager
Console is one of those tools. With this tool, an Oracle database can be easily
monitored and its structure can be clearly seen. In this section, we use Oracle
Enterprise Manager Console as a tool to help you understand Oracle Database
architecture. Part IV of this module provides the instructions on how to use these
Figure 1 is a snapshot of Oracle database server from the Oracle Enterprise
Manager Console. On the left side under Database folder, there are multiple
databases displayed. The blue highlighted database, YUDB, is further extended
to reveal all the components in the database. “System” indicates that the user,
system, logged in at the moment. Under YUDB, there are eight components,
instance, schema, security and storage, etc. Every Oracle database has the same
structural organization as shown in YUDB. In this section, each of these
components will be discussed. On the right side of Figure 1, it shows the
database name and communication information and also will be discussed later
when we discuss Oracle network.
Figure 1. The organization of an Oracle Database.
1. Database and instance.
When an Oracle database started, several events occur almost spontaneously,
including allocating memory, mounting database, and starting oracle
processes. After an Oracle database instance is up and running, users can
access their data in the database. A user process, including connection and
user session, would be established for the user as long as the user stay
connected. Even through this is an over simplified description of how an
Oracle database server works, it does strike two important facts about an
Oracle database instance. One is the allocation of system memory and the
other is the start up of both Oracle and user processes.
A. The memory architectures of an Oracle instance. The basic memory
structures of an Oracle instance include System Global Area (SGA),
Program Global Areas (PGA) and Software Code Areas. Each of these
memory areas has its own function and stores the information required to
accomplish user’s requests. The followings are the discussion of each of
theses memory areas.
a. System Global Area (SGA)
A SGA is allocated when an Oracle instance starts and shared by Oracle
processes and multiple users concurrently connected to the instance. It is
a group of memory structures, including the database buffer cache, the
redo log buffer, the shared pool, the large pool, the data dictionary cache
and other miscellaneous information. The information stored in SGA is
accessed each time when user requests are processed.
• Database Buffer Cache
The database buffer cache holds copies of data blocks read from
datafiles and is shared by all user processes concurrently connected to
the instance. The Figure 2 shows how a database buffer cache works
Figure 2. Database buffer cache in SGA. When a user process access
the database buffer cache to process a user request, it first searches the
cache to see whether the data required is available in the cache. It
reads the data from cache if it finds the data (called cache hit), or it
loads the data from the datafiles if it does not find the data (cache
miss). In the case of cache miss, the user process first find a free
buffer in the least recently used list (list 1 in Figure 2) of the cache and
load the data. If not, it signals the oracle process to move the dirty
buffer to write list. The oracle process then manages the write list and
writes the data to disk as necessary.
The properties of database buffer cache can be set or modified during
or after installation, including size of the database buffer cache and
multiple buffer pools. The more detailed discussion on this topic can
be found in Database concepts of Oracle documentation .
• Redo Log Buffer
The redo log buffer is the memory area allocated to hold the
information about changes made to the database. The information is
copied from user’s memory space by Oracle server process and is
stored in redo entries that is a log containing the changes made by
INSERT, UPDATE, DELETE, CREATE, ALTER, or DROP
operations. The data in the redo log buffer is written to a disk
periodically by an Oracle server process and used for database
recovery whenever it is necessary
Figure 3. the structure of the redo log buffer. The redo log buffer is a
circular memory. Oracle process, log writer, writes the data to the
redo log files in the database on a physical disk if there is not enough
room for newer redo entries.
• Shared Pool
The shared pool in the SGA consists of library cache, dictionary cache,
and control structures. It is shared among user processes. For
instance, data dictionary is stored in library cache and dictionary cache
in the shared pool and accessed by almost every database user process.
Others include the shared SQL areas, private SQL areas, PL/SQL
procedures and packages, and control structures such as locks and
library cache handles.
b. Program Global Areas (PGA)
A program global area (PGA) is a memory region containing data and
control information for a single process (server or background).
Consequently, a PGA is sometimes called a process global area. A PGA
is nonshared memory area to which a process can write. One PGA is
allocated for each server process. The PGA is exclusive to that server
process and is read and written only by Oracle code acting on behalf of
that process. A PGA is allocated by Oracle when a user connects to an
Oracle database and a session is created, though this varies by operating
system and configuration. A PGA always contains a stack space, which
is memory allocated to hold a session's variables, arrays, and other
information. If the instance is running without the multi-threaded server,
the PGA also contains information about the user's session, such as private
SQL areas. If the instance is running in multi-threaded server
configuration, this session information is not in the PGA, but is instead
allocated in the SGA.
B. Oracle and user processes
Generally speaking, a process is a mechanism in an operating system that
can execute a series of steps. In most cases, a memory area is allocated
specifically to run the process. In an Oracle database system, there are
two types of the processes running to accomplish the database tasks
requested by users. Oracle processes and user processes.
• User processes execute the customized applications, such as Oracle
forms and reports, or Oracle tool code, such as SQL*Plus.
• Oracle processes, including server processes and background
processes, execute the Oracle server code, such as Redo log writer.
How server processes and background processes are structured depends on
the configuration of an Oracle database server. Two most popular ways to
configure an Oracle database server are dedicated server and multi-
threaded server. In a dedicated server, for each user, a set of server
processes is dedicated to accomplish the user requests. While in a multi-
threaded server, multiple user processes share a set of Oracle server
processes to complete the tasks. Figure 4 shows how each architecture
Figure 4. Oracle server architecture.
Server processes are created when user log onto the database instance.
These processes parse and execute SQL statements or read the data from
the datafiles or return the result to the user. The background processes
include Database Writer (DBW0 or DBWn), Log Writer (LGWR),
Checkpoint (CKPT), System Monitor (SMON), Process Monitor
(PMON), Archiver (ARCn), Recoverer (RECO), Lock (LCK0), Job
Queue (SNPn), Queue Monitor (QMNn), Dispatcher (Dnnn), Server
(Snnn). Background processes are created automatically when an
instance is started. These processes work with the server processes to
complete user’s requests and also perform routine check up of the server
state or write log files and archive files. For the more detailed discussion
on the topics, see Oracle processes in Database concepts.
A user process is established when a user accesses the Oracle database
instance. A user process consists of a connection and a session. A
connection handles the communication of a user process to an Oracle
instance. A session connects a user to an Oracle instance and is
established when a user loges onto the server. It lasts from the time the
user connects until the time the user disconnects or exits the database
C. Monitor an Oracle database instance.
After an Oracle instance is created, it is routinely monitored by a DBA.
Oracle Enterprise Manager, powerful and easy to use, is one of the tools
used to monitor an Oracle database. In Figure 5 and 6, the information
about the instance, YUDB, is displayed by using Oracle Enterprise
Manager console. Learn more about how to use Oracle Enterprise
Manager console later in section IV.
Figure 5. Oracle instance, YUDB. On the left side of the Figure, under
YUDB-system, the instance is fully expended. Under session folder, there
are six background processes running currently and one user, system, logs
on the instance. More information can be displayed on the right if the
sessions folder or any individual session is highlighted. The configuration
is highlighted and the general information about instance is shown on the
right side of the figure, including state (open/shutdown), host name,
instance name and etc. Click on “All Initialization Parameters” button to
see all the parameter settings.
Figure 6. Instance memory and user session parameters. On the right side,
the memory settings are displayed and can be modified. 700 concurrent
users can log on the server.
2. Oracle network
Oracle database is a distributed system. Any tasks users request are shared
and accomplished by the client workstation and Oracle database server. The
communication between the client and the server is established by Oracle
network. The basic structure of Oracle network is shown in Figure 7.
Figure 7. Oracle network architecture.
Net8 uses either of the two ways to establish connection and data transmission
throughout the network. One way is the communication protocols (such as
TCP/IP), a set of standards that govern the transmission of data across a
network and the other is the application programmatic interfaces (APIs), a set
of subroutines that provide, in the case of networks, a means to establish
remote process-to-process communication via a communication protocol.
Net8 drivers provide an interface between Oracle processes running on the
database server and the user processes of Oracle tools running on other
computers of the network. In order to establish the communication between
client and server, the server must know there is a user request. This is done
through a network listener process. When an Oracle instance starts, a listener,
TNS listener, is up and running on the host as well. It opens a port (default
1521 for oracle database) and listens to the connection requests from users.
The listener determines whether it should use a shared server process or a
dedicated server process and establishes an appropriate connection and a
communication pathway to the database.
Oracle listener is configured using a file, listener.ora. Figure 8 shows two
parts of the file. TNSnames.ora is another file used to define the
communication information needed to connect to a database. Figure 9 shows
a portion of the file used to connect to the Oracle database, YUDB.
Figure 8. Listener.ora is used to configure the database listeners. In the
Figure, it is a portion of an example Listener.ora file. The LISTENER entry
defines the listening protocol address for a listener named LISTENER, and the
SID_LIST_LISTENER entry provides information about the database service,
including the global database name, the Oracle home location of the database,
and the Oracle System Identifier (SID) of the instance.
Figure 9. TNSnames.ora is used to configure the connection descriptors for
Oracle database and TNS in the filename stands for Transparent Network
Substrate. A connect descriptor is comprised of one or more protocol
addresses of the listener and connect data information for the destination
service. The following example shows a The ADDRESS portion contains the
listener protocol address, and the CONNECT_DATA portion contains the
destination service information. In this example, the destination service is a
database service named yudb.umuc.edu.
IN the section IV, you will learn how to configure an Oracle listener and
create a TNS name for an Oracle database server.
3. Database storage, tablespaces and datafiles.
Oracle database storage consists of both logical and physical structures.
Figure 10 shows the storage organization of an Oracle database displayed in
Oracle Enterprise Manager console. Tablespaces are the logical storage
structure in Oracle database associated with the physical files, datafiles. In
addition to datafiles, the physical structures that Oracle uses to store the data
and information about database include control files, redo log files and
archived files. Each Oracle database contains at least one rollback segment
used to store the changed data for read consistency and data recovery.
Figure 10. The storage organization of an Oracle Database.
Tablespaces are the only logical structure used to organize the physical
structure of the database. Each tablespace contains at least one datafile. The
size of a tablespace is determined by the size and number of datafiles in the
table space. In most cases, there are multiple tablespaces in an Oracle
database. There is no limitation on how the tablespaces are used in the
database. However, tablespaces are commonly used to organize the database
storage by storing highly related information together in the same tablespace.
For instance, system tablespace stores system information, such as data
dictionary. It is a good practice that each customized task has a designated
tablespase to store the information related to the task.
The database files are the physical storage of an Oracle database even though
it appears that the data is stored in tablespaces.
A. Control files.
Control files are not in any tablespaces. A control file contains the physical
structure of the database, the database name, names and locations of
associated databases and online redo log files, the timestamp of the database
creation, the current log sequence number and Checkpoint information. The
control file of an Oracle database is created at the same time as the database.
By default, at least one copy of the control file must be created during
database creation. On Window NT, Oracle creates multiple copies. The users
are encouraged to duplicate the control file in more then one locations to
ensure the safe guard critical information about the database.
Datafiles are always associated with a tablespace. They are the storage place
of a variety of data in an Oracle database. A tablespace may contain more
than one datafiles, however, a datafile can only be in one tablespace. The data
associated with schema objects, such as a table, in a tablespace is physically
stored in one or more of the datafiles as shown in Figure 11. In Figure 11, the
data in Example table is stored in both datafile 1 and 2. Therefore, a schema
object does not correspond to a specific datafile; rather, a datafile is a
repository for the data of any schema object within a specific tablespace.
Figure 11. Usage of datafiles in a tablespace.
The most crucial structure for
recovery operations is the online
redo log, which consists of two
or more pre-allocated files that
store all changes made to the
database as they occur. Every
instance of an Oracle database
has an associated online redo log
to protect the database in case of
an instance failure.
An archived redo log file is a
copy of one of the identical filled
members of an online redo log
group: it includes the redo entries
present in the identical members
of a group and also preserves the
group's unique log sequence
number. If you enable archiving,
LGWR is not allowed to reuse
and hence overwrite an online
redo log group until it has been
archived. Therefore, the archived
redo log contains a copy of every
group created since you enabled
The tablespace can be created in SQL*Plus with the DDL command
“CREATE TABLESPACE”. However, we will learn to create a tablespace
with Enterprise Manage Console.
Example of creating tablespaces
2. Schema and schema objects.
A schema is a collection of database objects, also known as schema objects,
including the logical structures like tables, views, sequences, stored
procedures, synonyms, indexes, clusters, and database links. Each user
account owns a schema and the objects created with this user account are
located in the schema. However, there is no relationship between a tablespace
and a schema. Objects in the same schema can be in different tablespaces,
and a tablespace can hold objects from different schemas.
A table is the basic unit of data storage in an Oracle database. The tables of a
database hold all of the user-accessible data.
Views do not actually contain or store data; rather, they are the pointers to the
data in the tables. The table that a view is based on is referred to as the base
table. Views can be based on tables and/or other views. There are two major
benefits using views instead of tables, one is that a view can limit access to the
data in a table and provide an additional level of table security. Second is that
a view hides the complexity of the data and simplify the query.
A materialized view, also known as snapshot, is built on query as well and
provides indirect access to table data. Unlike an ordinary view, which does
not take up any storage space or contain any data, a materialized view
contains the rows resulting from a query against one or more base tables or
views. A materialized view can be stored in the same database as its base
table(s) or in a different database.
A sequence generates a serial list of unique numbers for numeric columns of
a database's tables. Sequences simplify application programming by
automatically generating unique numerical values for the rows of a single
table or multiple tables.
Program units refer to stored procedures, functions, packages, triggers, and
A synonym is an alias for a schema object, such as a table, view, sequence, or
program unit. Synonyms can be either private or public. The can be used to
hide the real name and owner of a schema object, provide public access to a
Indexes are optional structures associated with tables, which can be created to
increase the performance of data retrieval. Just as the indexes in any books,
an Oracle indexes provide a faster way to locate specific information in the
database. Indexes are logically and physically independent of the data. They
can be dropped and created any time with no effect on the tables or other
indexes. If an index is dropped, all applications continue to function; however,
access to previously indexed data may be slower.
Clusters and Hash Clusters
In an Oracle database, there is no limitation on where database tables are
written in a datafile. If the data in closely related tables are physically
dispersed in the datafile, the performance of data sorting can be affected. In
this case, the optional structures of Clusters and hash clusters can be created to
improve the performance of data retrieval.
Clusters are groups of one or
more tables physically stored
together. The tables in a cluster
share common columns and are
often used together. These
related columns are called cluster
key and are indexed so that rows
of the cluster can be retrieved
with a minimum amount of I/O.
Like indexes, clusters do not
affect application design.
Whether or not a table is part of a
cluster is transparent to users and
Hash clusters also cluster table
data in a manner similar to
normal, index clusters (clusters
keyed with an index rather than a
hash function). However, a row
is stored in a hash cluster based
on the result of applying a hash
function to the row's cluster key
value. All rows with the same
key value are stored together on
disk. Hash clusters are a better
choice than using an indexed
table or index cluster when a
table is often queried with
equality queries (for example,
return all rows for department
10). For such queries, the
specified cluster key value is
hashed. The resulting hash key
value points directly to the area
on disk that stores the rows.
A dimension defines hierarchical (parent/child) relationships between pairs of
columns or column sets. Each value at the child level is associated with one
and only one value at the parent level. A dimension schema object is a
container of logical relationships between tables and does not have any data
storage assigned to it.
A database link is a named schema object that describes a path from one
database to another. Database links are implicitly used when a reference is
made to a global object name in a distributed database.
3. Other database components.
The detailed discussion of the following topics is beyond the scape of the
course. The more information can be found here in Oracle documentation.
Replication is the process of copying and maintaining database objects, such
as tables, in multiple databases that make up a distributed database system.
On-line Analytical Processing (OLAP) applications perform complex analysis
of data stored in a data warehouse.
Oracle JVM (Java Virtual Machine) stores and executes CORBA and EJB
components authored in Java. Client applications use a name service to access
A workspace is a virtual environment that one or more users can share to
make changes to the data in the database.
1. Introduction to Oracle security.
An Oracle database is a distributed system and there is always sensitive data in a
database. Therefore, Oracle database security is always an issue to be concerned.
The Oracle security becomes a bigger issue since currently the more and more
database applications move towards internet. In a typical client/server
environment, access to an Oracle database requires a user name and password.
The scope of a user access is determined by the database privileges pre-assigned
to the user account. Even though this is still an effective way to manage the
Oracle database access, it is not good enough to serve the internet users in current
technology world. For instance, in a multi-tier environment, a user may not be
allowed to log on an Oracle database directly, and the user name and password
used to log onto a web server may not be the same as that required to log on an
Oracle database. This raises a typical issue on synchronizing user credentials in a
broad network or “single sign on”. Furthermore, the protection of the user’s
credentials passing through internet becomes an even bigger issue to be
considered. Discussion on these issues is important, however, it is beyond the
coverage of this course. In this section, we will focus on how a user account and
its access privileges are managed to provide secure and limited access to a
customized Oracle database.
4. User accounts.
Any activities performed on an Oracle database require the user login. It is a
task for Oracle database administrators (DBA) to create, assign and manage a
user account. To establish a user account, a DBA creates a database user and
a password. However, it is not enough to even log into an Oracle database
with only user name and password. A set of database privileges must be
assigned to the user account, such as login privilege like “create sessions” and
use of a tablespace.
5. Database privileges: system, object privileges and roles.
In an Oracle database, privileges are the rights to access the database and
perform a database task, such as making a table or querying data from a table.
These privileges can be granted and revoked as well. There are two major
categories of database privileges, system, and object privileges. Each of them
is discussed below.
System privileges. A system privilege is the right to perform a particular
action, or to perform an action on any schema objects of a particular type.
For example, the privileges to create tablespaces and to delete the rows of
any table in a database are system privileges. There are over 60 distinct
Object Privileges. Object privilege is a privilege or right to perform a
particular action on a specific schema object, including tables, views,
sequences, procedures, functions and packages. Different object
privileges are available for different types of schema objects. For example,
the privileges to a table include “select”, “insert”, “update” and “delete”
etc. The privilege associated with a procedure is “execute”.
In an Oracle database, Privileges are defined in great details based on what
type of action each privilege could allow. Privileges can be grouped together.
Such a group of privileges is referred to as a role. A role, like privileges, can
be granted or revoked. In general, a role is used to manage the privileges for a
database application or to manage the privileges for a user group.
6. Create user and Grant or revoke a privilege.
A user account can be created with SQL DDL CREATE USER command.
The syntax is shown below,
CREATE USER user_name IDENTIFIED BY password
DEFAULT TABLESPACE tablespace_name
QUOTA size allocated ON tablespace_name
TEMPORARY TABLESPACE tablespace_name
QUOTA size allocated ON tablespace_name
In this syntax, only “CREATE USER user_name IDENTIFIED BY paswword”
is mandatory. The others can be defaulted by Oracle if they are not specified
during the creation. The user created with this command can not connect to the
database until the proper system privileges are granted to the user. The
privileges can be granted or revoked by the following DDL command,
GRANT privilege_name, ---- TO user_name;
REVOKE privilege_name, --- FROM user_name;
If a user account should be closed, DDL command, DROP USER user_name
can be used. However, it should be done with caution, because DROP USER
command essentially remove everything belong to the user from the database,
including entire schema. Execution of these commands in SQL*Plus can
establish a user account with litter effort. However, in this section, we use the
Oracle tool, Enterprise Manage Console, to create a user with proper database
privileges. Click the following link and follow the instruction to create a user.
The example of creating a user.
Note: please review the section IV to learn how to start and use Enterprise
Manage Console before doing these exercises.
7. Fine tune database access by creating roles.
The role, as stated above, is a collection of the database privileges, including
system and object privileges and can be granted to a user. A role can contain
other role or roles. Because of the flexibility in building a role, it provides the
opportunity to fine tune the access scope for a particular group of users.
The example of building a role.
Note: please review the section IV to learn how to start and use Enterprise
Manage Console before doing these exercises.
1. Introduction of Oracle database
Oracle data dictionary is one of the most important parts of an Oracle database. It
contains a set of read-only tables and is owned by the user, SYS and located in
system tablespace of the database. The data dictionary is uploaded into the SGA
(data dictionary cache) for fast access whenever an Oracle database instance
starts. It provides the information about almost every aspect of the Oracle
database, including the definitions of all schema objects in the database, default
values for columns, integrity constraint information, the names of Oracle users,
privileges and roles each user has been granted and auditing information, such as
who has accessed or updated various schema objects. The data dictionary of an
Oracle database consists of both base tables and user-accessible views. Only
Oracle has the right to directly write to these base tables because the importance
of the data to the database. The most data in these tables is stored in cryptic
format. Any users who need the information about the database can only query
the user-accessible views. Those views are also accessible to the users based
upon their own privileges. There are three types of the prefixes in front of view
names to indicate the scope of content. Most popular ones are listed below,
USER_ user's view (what is in the user's schema)
ALL_ expanded user's view (what the user can access)
DBA_ database administrator's view (what is in all users' schemas)
The data dictionary views with three types of the prefixes. They can be
composed by put prefix and name together. For instance, USER_TABLES
ALL_TABLES and DBA_TABLES. The followings are the views that are
often used to retrieve the information about schema objects.
USER_ , ALL_, DBA_CATALOG
USER_ , ALL_, DBA_CONSTRAINTS
USER_ , ALL_, DBA_CONS_COLUMNS
USER_ , ALL_, DBA_ERRORS
USER_ , ALL_, DBA_INDEXES
USER_ , ALL_, DBA_OBJECTS
USER_ , ALL_, DBA_SEQUENCES
USER_ , ALL_, DBA_SYNONYMS
USER_ , ALL_, DBA_TABLES
USER_ , ALL_, DBA_TRIGGERS
USER_ , ALL_, DBA_USERS
USER_ , ALL_, DBA_VIEWS
USER_ , DBA_TABLESPACES
Dynamic performance tables are not true tables, and they should not be accessed
by common users. However, database administrators can query and create views
on the tables and grant access to those views to other users. These views are
sometimes called fixed views because they cannot be altered or removed by the
SYS owns the dynamic performance tables; their names all begin with V_$.
Views are created on these tables, and then public synonyms are created for the
views. The synonym names begin with V$. For example, the V$DATAFILE view
contains information about the database's datafiles, and the V$FIXED_TABLE
view contains information about all of the dynamic performance tables and views
in the database.
2. Use GUI tool to view and manage
Oracle provides a set of GUI tools to manage an Oracle database. In Window
NT/2000, almost every task can be accomplished with one or the other GUI tools
Oracle provides. In this section, we learn Oracle Enterprise Manager Console
tool, one of most powerful and complete database management system. We also
learn how to create an Oracle database and configure TNS listener and TNS
names using database configuration assistant and net configuration assistant.
Oracle enterprise Manager Console.
Create a database after installation and configure Oracle Network.
8. Suggested reading.
Database Administration Guide
9. Review questions.
• What are database instance, SGA and ?
• How is security enforced in Oracle database?
• How to create user?
• What are roles, system privileges and object privileges?
• What privileges are there in the roles, connect and resource respectively?
• What are tablespaces and datafiles?
• How to create tablespace?
• What is data dictionary?
• What is the deference in USER_ , ALL_ , AND DBA_ views or tables.
• What a user who is not DBA sees if he accesses USER_TABLES and