Save and restore processing for a distributed relational database

 

Saving and restoring data and programs allows recovery from a program or system failure, exchange of information between systems, or storage of objects or data offline. A comprehensive backup policy at each system in the distributed relational database network ensures that a system can be restored and quickly made available to network users in the event of a problem.

Saving the system on external media, such as tape, protects system programs and data from disasters, such as fire or flood. However, information can also be saved to a disk file called a save file. A save file is a disk-resident file used to store data until it is used in input and output operations or for transmission to another i5/OS^® operating system over communication lines. Using a save file allows unattended save operations because an operator does not need to load tapes. In a distributed relational database, save files can be sent to another system as a protection method.

When information is restored, the information is written from tape or a save file into auxiliary storage where it can be accessed by system users.

The i5/OS operating system has a full set of commands to save and restore your database tables and SQL objects:

• The Save Library (SAVLIB) command saves one or more collections

• The Save Object (SAVOBJ) command saves one or more objects such as SQL tables, views and indexes

• The Save Changed Object (SAVCHGOBJ) command saves any objects that have changed since either the last time the collection was saved or from a specified date

• The Save Save File Data (SAVSAVFDTA) command saves the contents of a save file

• The Save System (SAVSYS) command saves the operating system, security information, device configurations, and system values

• The Restore Library (RSTLIB) command restores a collection

• The Restore Object (RSTOBJ) command restores one or more objects such as SQL tables, views and indexes

• The Restore User Profiles (RSTUSRPRF), Restore Authority (RSTAUT) and Restore Configuration (RSTCFG) commands restore user profiles, authorities, and configurations saved by a Save System (SAVSYS) command

• Saving and restoring indexes in the distributed relational database environment
  Restoring an SQL index can be faster than rebuilding it. Although times vary depending on a number of factors, rebuilding a database index takes approximately one minute for every 10 000 rows.

• Saving and restoring security information in the distributed relational database environment
  You can use a variety of CL commands to save and restore security information.

• Saving and restoring SQL packages in the distributed relational database environment
  When an application program that refers to a relational database on a remote system is precompiled and bound, an SQL package is created on the application server (AS) to contain the control structures necessary to process any SQL statements in the application.

• Saving and restoring relational database directories
  The relational database directory is not an i5/OS object. Instead, it is made up of files that are opened by the system at initial program load (IPL) time.

 

Parent topic:

Recovery support for a distributed relational database

 

Related concepts

Troubleshooting transactions and commitment control

 

Related tasks

Working with commitment definitions in a distributed relational database

 

Related reference

Transaction recovery through commitment control
DECLARE CURSOR
Start Commitment Control (STRCMTCTL) command
Work with Commitment Definitions (WRKCMTDFN) command
Save Object (SAVOBJ) command
Save Library (SAVLIB) command
Save Changed Object (SAVCHGOBJ) command
Save Save File Data (SAVSAVFDTA) command
Save System (SAVSYS) command
Restore Library (RSTLIB) command
Restore Object (RSTOBJ) command
Restore User Profiles (RSTUSRPRF) command
Restore Authority (RSTAUT) command
Restore Configuration (RSTCFG) command