Fujitsu UDS/SQL V2.5 用户手册
Database distribution
Database design
48
U929-J-Z125-9-76
Reasons for distributing databases among several computers within a network:
–
Adaptability
Work processes can be optimized for the local computer center, and data storage can
be adapted even better to the organization of the company.
be adapted even better to the organization of the company.
–
Availability
When distributed databases are used, the data resources are more easily available
since especially important and frequently used data can be stored in more than one
system, and the copies coupled together. If the backups are stored at different locations
and one of the systems fails, the data can still be accessed in other systems.
since especially important and frequently used data can be stored in more than one
system, and the copies coupled together. If the backups are stored at different locations
and one of the systems fails, the data can still be accessed in other systems.
–
Reduced cost
Costs are cut when fewer data stations require a continuous link to the central computer
center. Most of the data required can be accessed locally; only occasionally is it
necessary to access remote data.
center. Most of the data required can be accessed locally; only occasionally is it
necessary to access remote data.
Figure 8: Accessing databases in another configuration within the same host
AP1
APn
...
DB1
DBn
...
Configuration 1
DBH
UDS-D
AP1
APn
...
DB1
DBn
...
Configuration 2
UDS-D
DBH
Host 1