| Oracle® Database Installation Guide 10g Release 2 (10.2) for IBM zSeries Based Linux Part Number B25400-01 |
|
|
View PDF |
| Oracle® Database Installation Guide 10g Release 2 (10.2) for IBM zSeries Based Linux Part Number B25400-01 |
|
|
View PDF |
This chapter describes the different types of Oracle Database installations that you can perform, and issues that you should consider before installing the software. It includes information about the following topics:
The Oracle Database installation process consists of the following phases:
Read the release notes: Read the Oracle Database 10g release 2 (10.2) release notes before you begin the installation. The release notes are available with the platform-specific documentation. The latest version of the release notes is available on Oracle Technology Network at:
http://www.oracle.com/technology/documentation
Planning the installation: This chapter describes the Oracle products that you can install and issues that you must consider before starting the installation.
You can also refer to Appendix G which covers frequently asked questions about installing Oracle Database components, such as how to install Oracle Database if the site uses Oracle applications or if you need multiple Oracle Database client connections.
Completing preinstallation tasks: Chapter 2 describes preinstallation tasks that you must complete before installing the product.
Installing software: Use the following section to install Oracle Database:
Chapter 3 describes how to use Oracle Universal Installer to install Oracle Database and Automatic Storage Management.
Appendix A provides information on performing noninteractive (silent) installations, which you may want to use if you need to perform multiple installations of Oracle Database.
Appendix F provides information on cloning Oracle home.
Appendix D describes globalization support information.
Appendix E provides troubleshooting advice in case you encounter problems with the installation.
Chapter 6 describes how to remove Oracle Database.
Completing postinstallation tasks: Chapter 4 describes recommended and required post-installation tasks.
Get started using Oracle Database: Chapter 5 describes how to check the contents of the installed Oracle Database, how to start various tools, and how to locate various files. You can also read Appendix B on network attached storage devices, which you can use to store Oracle database files and Oracle software. Appendix B describes the Optimal Flexible Architecture, which is a set of guidelines that ensure reliable Oracle installations that require little maintenance, and Appendix C explains how to manage Oracle Database port numbers.
You can choose different installation methods to install Oracle Database, as follows:
When you use the interactive method to install Oracle Database, Oracle Universal Installer displays a series of screens that enable you to specify all of the required information to install the Oracle Database software and optionally create a database.
With Oracle Database 10g release 10.2 on , Oracle Universal Installer provides two interactive methods that you can use to install Oracle Database:
Basic Installation method:
Select this installation method if you want to quickly install Oracle Database. This installation method requires minimal user input. It installs the software and optionally creates a general-purpose database using the information that you specify on the screen. It is the default installation method.
Advanced Installation method:
Select this installation method if you want to complete any of the following tasks:
Perform a custom software installation, or choose a different database configuration
The Available Product Components installation screen automatically selects the components most customers need in their Oracle Database installation. It also lists several components that are not selected by default, but which you may want to include. To find the listing of available components, select Advanced, and then in the Installation Type screen, select Custom.
Upgrade an existing database
Select a database character set or different product languages
Create the EXAMPLE tablespace during the installation
Create a database on a different file system from the software
Configure Automatic Storage Management or use raw devices for database storage
Specify different passwords for administrative schemas
Configure automated backups or Oracle Enterprise Manager notifications
By creating a response file and specifying this file when you start Oracle Universal Installer, you can automate some or all of the Oracle Database installation. These automated installation methods are useful if you need to perform multiple installations on similarly configured systems or if the system where you want to install the software does not have X Window system software installed.
When you use a response file, you can run Oracle Universal Installer in the following modes, depending on whether you specify all of the required information or not:
Silent Mode: Oracle Universal Installer runs in silent mode if you use a response file that specifies all required information. None of the Oracle Universal Installer screens are displayed.
Suppressed Mode: Oracle Universal Installer runs in suppressed mode if you do not specify all required information in the response file. Oracle Universal Installer displays only the screens that prompt for the information that you did not specify.
For more information about these modes and about how to complete an installation using response files, refer to Appendix A.
Note:
Oracle Client is installed separately. You cannot install Oracle Database Client during an Oracle Database installation.You can choose one of the following installation types when installing Oracle Database 10g:
See Also:
For more information about the features available with each Oracle Database edition and for information about licensing, refer to the Oracle Database Licensing Information guideEnterprise Edition: Installs licensable Oracle Database options and database configuration and management tools in addition to all of the products that are installed during a Standard Edition installation. It also installs products most commonly used for data warehousing and transaction processing.
Standard Edition: Installs an integrated set of management tools, full distribution, replication, Web features, and facilities for building business-critical applications.
Note:
If you purchased a Standard Edition license, and you perform a Custom installation, then ensure that you install only the components covered by the Standard Edition license.Custom: Enables you to select the individual components that you want to install from the list of all available components.
During the installation, you can choose whether you want to create an Oracle database as part of the installation. If you choose to create an Oracle database, then Oracle Universal Installer uses Database Configuration Assistant to create it. You can choose to create one of the preconfigured database types, which are designed for a variety of different applications, modify one of the preconfigured database types, or create a customized database to suit your requirements.
This section describes the following database configuration options:
Oracle provides the following preconfigured database types that you can create or customize during the installation:
General Purpose
Transaction Processing
Data Warehouse
Refer to the online help provided by either Oracle Universal Installer or Database Configuration Assistant for a description of these preconfigured database types.
Oracle Universal Installer runs Database Configuration Assistant in one of two modes, depending on the choices that you make during the installation:
Noninteractive mode
If you choose either the Enterprise Edition or Standard Edition installation type, then choose to create a preconfigured database type, Oracle Universal Installer prompts you for the minimum amount of information required to create a database of the type you choose. It then runs Database Configuration Assistant in noninteractive mode to create the database after it installs the software.
Interactive mode
If you choose the Custom installation type or choose the Advanced database configuration option, then Oracle Universal Installer does not prompt you for database information. Instead, it installs the software and then runs Database Configuration Assistant in interactive mode. Using the screens in Database Configuration Assistant, you can either modify one of the preconfigured database types or create a custom database and specify precisely how you want to configure it.
Note:
If you choose this method to create a database, then click Help on any of the Database Configuration Assistant screens for a description of the information that you must specify on that screen.If you decide not to create a database during the installation, then you can use Database Configuration Assistant to create one after you have installed the software. For more information about using Database Configuration Assistant to create a database after installation, refer to the Oracle Database 2 Day DBA manual.
This release of Oracle Database provides options that you can choose during installation to simplify database administration tasks. These options include:
The following sections describe these options.
If you choose to create a database during the installation, you can specify one of three storage options for database files:
If you choose the file system option, then Database Configuration Assistant creates the database files in a directory on a file system mounted on the computer. Oracle recommends that the file system you choose be separate from the file systems used by the operating system or the Oracle software. The file system that you choose can be any of the following:
A file system on a disk that is physically attached to the system
If you are creating a database on basic disks that are not logical volumes or RAID devices, then Oracle recommends that you follow the Optimal Flexible Architecture (OFA) recommendations described in Appendix B and distribute the database files over more than one disk.
A file system on a logical volume manager (LVM) volume or a RAID device
If you are using multiple disks in an LVM or RAID configuration, then Oracle recommends that you use the stripe and mirror everything (SAME) methodology to increase performance and reliability. Using this methodology, you do not need to specify more than one file system mount point for database storage.
A network file system (NFS) mounted from a certified network attached storage (NAS) device
You can store database files on NAS devices provided that the NAS device is certified by Oracle.
See Also:
The "Using Network Attached Storage or NFS File Systems" section for more information about certified NAS and NFS devicesIf you choose the Custom installation type or the Advanced database creation option, then you can also choose to use the Oracle-managed files feature with the new database. If you use this feature, then you need to specify only the database object name instead of file names when creating or deleting database files.
See Also:
Oracle Database Administrator's Guide for more information about Oracle-managed filesAutomatic Storage Management is a high-performance storage management solution for Oracle Database files. It simplifies the management of a dynamic database environment, such as creating and laying out databases and managing disk space.
Automatic Storage Management can be used with single database installations, multiple database installations, and in Oracle Real Application Clusters (RAC) environments. It can be used with databases created in Oracle Database 10g release 1 (10.1.0.3 or later). However, Oracle Database 10g release 2 (10.2) databases can use Automatic Storage Management from Oracle Database 10g release 1 (10.1). If a site has multiple single-instance databases, then you can use Oracle Clusterware to consolidate multiple islands of databases into a single clustered pool of storage managed by Automatic Storage Management. Automatic Storage Management manages the storage of all database files, such as redo logs, control files, data pump export files, and so on. However, it does not manage Oracle Database executable binary files.
At a high level, implementing Automatic Storage Management involves allocating partitioned disks for Oracle Database with preferences for striping and mirroring. Automatic Storage Management manages the disk space for you. This helps avoid the need for traditional disk management tools such as Logical Volume Managers (LVM), file systems, and the numerous commands necessary to manage both. The synchronization between Automatic Storage Management and the database instance is handled by Oracle Cluster Synchronization Services (CSS).
The following are components of an Automatic Storage Management installation:
A disk group is a set of disk devices that Automatic Storage Management manages as a single unit. Each disk device can be an individual physical disk, a multiple disk device such as a RAID storage array or logical volume, or even a partition on a physical disk. However, in most cases, disk groups consist of one or more individual physical disks. To enable Automatic Storage Management to balance I/O and storage efficiently within the disk group, you must ensure that all devices in the disk group have similar, if not identical, storage capacity and performance.
You can set the redundancy and striping attributes of individual file types within a disk group by using ASM disk group templates. When you create a disk group, Automatic Storage Management creates a set of default templates for that disk group. Default template settings depend on the disk group type. For example, the default template for control files for a normal redundancy disk group sets three-way mirroring. All other file templates are two-way mirrored. For a high redundancy disk group, the default mirroring cannot be changed; that is, all files are always three-way mirrored in a high redundancy disk group. You can modify the default templates to suit your site's needs. See Oracle Database Administrator's Guide for more information.
Automatic Storage Management spreads data evenly across all the devices in the disk group to optimize performance and utilization. You can add or remove disk devices from a disk group without shutting down the database. When you add or remove disks, Automatic Storage Management rebalances the files across the disk group. You can create multiple disk groups to handle specific tasks, such as backup and recovery operations, in addition to regular file storage activities.
When you add a device to a disk group, you can specify a failure group for that device. Failure groups identify disk devices that have common failure characteristics, for example, devices that are attached to the same controller. If the controller fails, then all devices attached to it become unavailable. By default, each device also belongs to its own failure group. By using the failure groups you specify, Automatic Storage Management can distribute data among the devices in the disk group to minimize the risk of data loss caused by component failures.
The ASM instance manages ASM disk groups. This instance must be running before you can start a database instance that uses Automatic Storage Management. When you choose Automatic Storage Management as a database storage mechanism, this instance is created and started, if necessary. For a single-instance Oracle Database installation, you only need one Automatic Storage Management instance, regardless of the number of database instances on the system. The ASM instance on any node in a single cluster can handle any combination of disk group types.
General Steps for Installing Automatic Storage Management
To install Automatic Storage Management, you use Oracle Universal Installer. This installation guide provides the following general steps for installing Automatic Storage Management:
Determine the disk requirements of the site and, if necessary, create one or more disk partitions for Automatic Storage Management.
"Preparing Disk Groups for an Automatic Storage Management Installation" provides guidelines on how to determine the disk requirements of the site.
Run Oracle Universal Installer to install and create an Automatic Storage Management instance and to create Automatic Storage Management disk groups.
"Step 1: Reviewing Automatic Storage Management Installation Considerations" provides guidelines on where to install Automatic Storage Management and other installation considerations. "Step 2: Creating the Automatic Storage Management Instance and Disk Groups" describes how to create an Automatic Storage Management instance and disk groups.
After you create an Automatic Storage Management instance and its associated disk groups, subsequent databases that you create will be able to use Automatic Storage Management for file storage management. If you have databases that were created before you installed Automatic Storage Management, then you can migrate them to Automatic Storage Management by using the Enterprise Manager Migrate Database Wizard. This wizard is available in Enterprise Manager Grid Control or Database Control. Alternatively, you can use Oracle Database Recovery Manager (RMAN) to perform the migration.
Create the databases that you want to use Automatic Storage Management.
"Step 3: Installing Oracle Database to Use with Automatic Storage Management" on page 3-15 describes how to create and a database for Automatic Storage Management.
Test the Automatic Storage Management installation.
"Step 3: Installing Oracle Database to Use with Automatic Storage Management" provides a simple test you can try to check that the Automatic Storage Management installation was successful. "Managing Automatic Storage Management" explains how to start and access Automatic Storage Management and which Oracle Database tools you can use to manage it.
See Also:
Oracle Database 2 Day DBA for a general overview, from a non-platform perspective, of Automatic Storage Management
Oracle Database New Features for information about new features in this release of Automatic Storage Management
Oracle Database Administrator's Guide for a more detailed description of Automatic Storage Management
The Oracle Technology Network Web site, for additional information on Automatic Storage Management, which you can visit at
Raw devices are disk partitions or logical volumes that have not been formatted with a file system. When you use raw devices for database file storage, Oracle writes data directly to the partition or volume, bypassing the operating system file system layer. For this reason, you can sometimes achieve performance gains by using raw devices. However, because raw devices can be difficult to create and administer, and because the performance gains over modern file systems are minimal, Oracle recommends that you choose Automatic Storage Management or file system storage in preference to raw devices.
To simplify database administration, Oracle provides a Web-based management tool called Oracle Enterprise Manager. There are two ways that you can deploy Oracle Enterprise Manager:
Deploy Oracle Enterprise Manager 10g centrally in the environment
To deploy Oracle Enterprise Manager centrally, you must install at least one Oracle Management Repository and one Oracle Management Service within the environment, then install an Oracle Enterprise Management Agent on every computer that you want to manage. You can then use a single HTML interface to manage and monitor software and hardware targets on all of those systems. Targets can include Oracle databases, application servers, Net listeners, and third-party software. This single interface is called Oracle Enterprise Manager Grid Control (or simply Grid Control).
Note:
Oracle Enterprise Manager 10g is available separately in the Oracle Database media pack. For more information about Oracle Enterprise Manager 10g, refer to the Oracle Enterprise Manager 10g Concepts manual and the Oracle Enterprise Manager 10g Installation and Basic Configuration manual.Deploy Oracle Enterprise Manager Database Control locally on the database system
Oracle Enterprise Manager Database Control software is installed by default with every Oracle Database installation except Custom. During a Custom installation, you can choose not to install Oracle Enterprise Manager Database Control. However, Oracle recommends that you do install it. This local installation provides a Web-based interface called Oracle Enterprise Manager Database Control. The Database Control is similar in function to the Grid Control, but it can manage only a single database. If you want to administer more than one database on this system, then you must either configure a separate Database Control for each database, or install Oracle Enterprise Manager 10g Grid Control.
This section contains the following topics:
When you choose to create a preconfigured database during the installation, you must select the Oracle Enterprise Manager interface that you want to use to manage the database. The following options are available:
Use Grid Control for central database management
This option is available only if an Oracle Management Agent is installed on the system. When Oracle Universal Installer detects an Oracle Management Agent on the system, you can choose this option and specify the Oracle Management Service that you want to use to manage the database.
If an Oracle Management Agent is not installed, then you must choose to use Database Control to manage the database. However, if you install Oracle Management Agent after you install Oracle Database, then you can then use Grid Control to manage this database.
Use Database Control for local database management
This option is selected by default if an Oracle Management Agent is not installed on the system. However, even if a Management Agent is installed, you can still choose to configure Database Control to manage the database.
If you choose the Advanced database configuration option or choose to create a database during a Custom installation, then Oracle Universal Installer runs Database Configuration Assistant in interactive mode. Using a screen in Database Configuration Assistant, you can specify the Oracle Enterprise Manager interface that you want to use to manage the database. Alternatively, you can also choose not to configure the database with Enterprise Manager.
Note:
Oracle recommends that you configure the database to use Enterprise Manager during installation. However, if you choose not to configure the database to use Enterprise Manager during the installation, then you can use Database Configuration Assistant after the installation to configure the database to use it.Oracle Enterprise Manager Database Control provides a Web-based user interface that enables you to monitor, administer, and maintain an Oracle database. You can use it to perform all of the database administration tasks. You can also use it to determine information about the database, such as:
Instance name, database version, Oracle home location, media recovery options, and other instance data
Current instance availability
Database alert information
Session and SQL-related performance information
Space usage metrics
In addition, it provides you with automatic notification of security alerts and it provides the ability to download and apply patches for the software.
If you choose to use Oracle Enterprise Manager Database Control during the installation, then you can optionally enable automated database backups that use the Oracle-suggested default backup strategy.
Note:
You do not have to enable automated backups during the installation. If you prefer, you can use Oracle Enterprise Manager Database Control or Grid Control to configure automated backups after you install the software and create a database.This section contains the following topics:
If you enable automated backups, then Oracle Enterprise Manager schedules a daily backup job that uses Oracle Recovery Manager (RMAN) to back up all of the database files to an on-disk storage area called the flash recovery area. The first time the backup job runs, it creates a full backup of the database. Subsequent backup jobs perform incremental backups, which enable you to recover the database to its state at any point during the preceding 24 hours.
To enable automated backup jobs during installation, you must specify the following information:
The location of the flash recovery area
You can choose to use either a file system directory or an Automatic Storage Management disk group for the flash recovery area. The default disk quota configured for the flash recovery area is 2 GB. For Automatic Storage Management disk groups, the required disk space depends on the redundancy level of the disk group that you choose. Chapter 2 describes how to choose the location of the flash recovery area and identifies its disk space requirements.
An operating system user name and password for the backup job
Oracle Enterprise Manager uses the operating system credentials that you specify when running the backup job. The user name that you specify must belong to the UNIX group that identifies database administrators (the OSDBA group, typically dba). The Oracle software owner user (typically oracle) that you use to install the software is a suitable choice for this user. Chapter 2 describes the requirements for the OSDBA group and Oracle software owner user and describes how to create them.
If you enable automated backups after choosing one of the preconfigured databases during the installation, then automated backup is configured with the following default settings:
The backup job is scheduled to run nightly at 2 a.m.
The disk quota for the flash recovery area is 2 GB.
If you enable automated backups by using Database Configuration Assistant, either during or after the installation, then you can specify a different start time for the backup job and a different disk quota for the flash recovery area.
For information about using Oracle Enterprise Manager Database Control to configure or customize automated backups or to recover a backed up database, refer to the Oracle Database 2 Day DBA manual.
For more detailed information about defining a backup strategy and backing up and recovering Oracle databases, refer to the Oracle Database Backup and Recovery Basics manual or Oracle Database Backup and Recovery Advanced User's Guide.
If you choose to use the Oracle Enterprise Manager Database Control during the installation, then you can configure Enterprise Manager to send e-mail when specific events occur. These events can include occurrences such as disk space reaching a critical limit (a threshold), or a database shutting down unexpectedly.
If you choose to enable e-mail notifications, then you must specify the following information:
The host name of a Simple Mail Transfer Protocol (SMTP) server
The e-mail address that should receive the alerts
The e-mail address that you specify could belong to an individual or it could be a shared e-mail account or a distribution list.
You can use Enterprise Manager Database Control to set up, change, or customize e-mail notifications after you have created the database.
This section contains information that you should consider before deciding how to install this product. It contains the following sections:
The platform-specific hardware and software requirements included in this installation guide were current at the time this guide was published. However, because new platforms and operating system software versions might be certified after this guide is published, review the certification matrix on the OracleMetaLink Web site for the most up-to-date list of certified hardware platforms and operating system versions. The OracleMetaLink Web site is available at the following URL:
https://metalink.oracle.com
If you do not have a current Oracle Support Services contract, then you can access the same information at the following Web site:
http://www.oracle.com/technology/support/metalink/content.html
This product supports multiple Oracle homes. This means that you can install this release or previous releases of the software more than once on the same system, in different Oracle home directories.
You must install this product into a new Oracle home directory. You cannot install products from one release of Oracle Database into an Oracle home directory of a different release. For example, you cannot install release 10.2 software into an existing Oracle9i Oracle home directory. If you attempt to install this release into an Oracle home directory that contains software from an earlier Oracle release, then the installation fails.
You can install this release more than once on the same system if each installation is installed in a separate Oracle home directory.
The first time you install Oracle Database 10g on a system, the installation configures and starts a single-node version of the Oracle Cluster Synchronization Services (CSS) daemon. The CSS daemon is required to enable synchronization between an Automatic Storage Management instance and the database instances that rely on it for database file storage. By default, Oracle Universal Installer does not configure Oracle Cluster Synchronization Services. Oracle Universal Installer configures these services only if you choose Automatic Storage Management as a storage or recovery option. Because it must be running before any Automatic Storage Management instance or database instance starts, it is configured to start automatically when the system boots.
For Oracle Real Application Clusters installations, the CSS daemon is installed with Oracle Clusterware in a separate Oracle home directory (also called the Clusterware home directory). For single-node installations, the CSS daemon is installed in and runs from the same Oracle home as Oracle Database.
If you have installed Oracle Cluster Synchronization Services from the same Oracle home as Oracle Database, then use caution when removing Oracle Database 10g software from the system. Before you remove an Oracle home directory that contains Oracle Database 10g, you must either delete the CSS daemon configuration, or if necessary, reconfigure the CSS daemon to run from another Oracle home directory.
See Also:
The "Reconfiguring Oracle Cluster Synchronization Services" section for more information about deleting or reconfiguring the Oracle CSS daemonNote:
If you plan to have more than one Oracle Database 10g installation on a single system and you want to use Automatic Storage Management for database file storage, then Oracle recommends that you run the CSS daemon and the Automatic Storage Management instance from the same Oracle home directory and use different Oracle home directories for the database instances.Oracle Database 10g must be able to verify that writes to a disk are completed successfully. NFS file systems, including file systems on NAS devices, may not be able to guarantee that writes to a disk are completed successfully, and this may lead to possible data file corruption. Oracle recommends that you do not store files on NFS mounted file systems unless the storage vendor and storage device are listed in the Oracle Storage Compatibility Program list. This list is available from the following Web site:
http://www.oracle.com/technology/deploy/availability/htdocs/oscp.html
If a storage device is supported, then you can use it to store Oracle software files, Oracle database files, or both.
See Also:
Appendix B for guidelines about using NFS and NAS devices for Oracle software or database filesFor information about upgrading a previous release of Oracle Database to Oracle Database 10g release 2 (10.2), refer to Oracle Database Upgrade Guide. The following sections provide additional platform-specific upgrade information that you should review before upgrading an existing database:
Note:
The information in this section does not apply to an upgrade of a release 9.0.1 or later release of Oracle Database.Before you upgrade an existing database that uses the AL24UTFFSS character set, you must upgrade the database character set to UTF8. Oracle recommends that you use the Character Set Scanner (csscan) utility for data analysis before attempting to upgrade the existing database character set.
The Character Set Scanner utility checks all character data in the database and tests for the effects of, and problems with, changing the character set encoding. Before running the Character Set Scanner utility, set the shared library path environment variable for the platform to include the $ORACLE_HOME/lib directory. The shared library path environment path that you need to set is LD_LIBRARY_PATH.
Caution:
AL32UTF8 is the Oracle Database character set that is appropriate for XMLType data. It is equivalent to the IANA registered standard UTF-8 encoding, which supports all valid XML characters.Do not confuse Oracle Database database character set UTF8 (no hyphen) with database character set AL32UTF8 or with character encoding UTF-8. Database character set UTF8 has been superseded by AL32UTF8. Do not use UTF8 for XML data. UTF8 supports only Unicode version 3.1 and earlier; it does not support all valid XML characters. AL32UTF8 has no such limitation.
Using database character set UTF8 for XML data could potentially cause a fatal error or affect security negatively. If a character that is not supported by the database character set appears in an input-document element name, then a replacement character (usually "?") is substituted for it. This will terminate parsing and raise an exception.
If you have the 8.1.7, 9.0.1, 9.2.0, or 10.1 release of Oracle Database installed on Red Hat Enterprise Linux 2.1, then you must first upgrade the operating system to Red Hat Enterprise Linux 4 (update 2) before you upgrade the database. To do this, perform any one of the following procedures:
See Also:
Oracle Database Upgrade GuideUpgrade the operating system. Then, upgrade the database either manually or by using Oracle Database Upgrade Assistant. The detailed information on preserving database environment while upgrading the operating system is available at the following URL:
http://www.oracle.com/technology/tech/linux/pdf/rhel_23_upgrade.pdf
Copy the database files. This procedure involves the following steps:
Copy the database files from the computer running Red Hat Enterprise Linux 2.1 to the one running Red Hat Enterprise Linux 3.0.
Re-create the control files on the computer running Red Hat Enterprise Linux 3.0.
Manually upgrade the database.
Note:
You cannot use Oracle Database Upgrade Assistant if you follow this method. However, this method lets you easily revert to the earlier database.Upgrade the database by using the Export/Import utilities.
