Figure 22-1 shows the HiRDB system configuration that is provided by simple installation.
Figure 22-1 HiRDB system configuration provided by simple installation
The system files and RDAREAs that are important components of a HiRDB system are explained briefly as follows.
A file used by a HiRDB system to recover the system status in the event of an error is called a system file. Table 22-3 lists the types of HiRDB system files.
Table 22-3 Types of HiRDB system files
Type of file | Role |
---|---|
System log file | Stores historical information about database updating. |
Synchronization point dump file | Stores HiRDB management information. Can be used with system log files during error recovery. |
Status file | Stores system status information needed in order to restart HiRDB. |
The unit of storage for database information is called an RDAREA. One RDAREA may consist of multiple HiRDB-dedicated files in a HiRDB file system area. Table 22-4 lists the principal types of RDAREAs.
Table 22-4 Principal types of RDAREAs
RDAREA | Role |
---|---|
System RDAREA | Stores system information, such as dictionary tables. |
User RDAREA | Stores tables and indexes that are created by a user. |
User LOB RDAREA | Stores in units of KB, MB, or GB large amounts of table and index data (as binary data) created by a user. |