Database Reference
In-Depth Information
Issues related to server and data storage equipment
: Your database server and data storage
devices should be adequate to support all the business activities. Based on the number of users who
will be using the database and how many of them will simultaneously log on to the same database,
and the time requirements for operations, your decision on the selection of hardware will be quite
diferent. For example, for a database to be used to store information for a large company, database
reliability, availability, and security are the major concerns. You may be required to mirror your
database on multiple servers and store data on a redundant array of inexpensive disks (RAID) stor-
age structure. Additional devices may also be needed for database backup and recovery. Protecting
data stored on your database is another important issue to be addressed. For valuable data, extra
equipment should be added for data protection.
Issues related to database access
: he way in which users access a database also inluences
the physical design. For example, if your database users need to access the database through the
Internet or local area network, you need to specify the interface for accessing remote data from the
client side. Accessing data through GUI often requires more network capacity. Knowing the data
transaction rate will help you decide if the network can handle the data communication tasks.
here are some design issues involved in data sharing by diferent types of database applications
over diferent types of computer systems. You need to determine what software and hardware to
install to support the communication needs. It is also helpful if you know how the data are used
in the business process. he requirements for the hardware and software are diferent depending
on whether your database will be used for decision support or for data transactions. You need to
choose the right tools in your database for data conversion. Also, for users to log on to your data-
base, you need to determine which groups of users are allowed to access what kinds of data. Tools
used to limit accessing certain sensitive data should be included in your database system.
Issues related to data characteristics
: Knowing the characteristics of data in your future
database will help you select the server and storage hardware. As a database designer, you need
to know how large the existing data sets are and what the annual growth rate is. he data type is
also an important factor in helping you determine what kind of server to use. For example, if your
database will be used to store data with the blob data type, which requires more storage space than
other types and whose growth of data size is fairly fast, you need to build your database on a server
with high expandability. If your database can only store a limited amount of data, you need to
determine how long the data will have to be stored in the database and ind a way to move the old
data out of the database and place them in another data storage facility.
Windows Azure
: Traditionally, the physical design is carried out around a company's IT infra-
structure. In a cloud computing environment, the physical design can be greatly simpliied. he
required IT infrastructure will be provided by the cloud provider. Especially, Windows Azure pro-
vides not only hardware such as networks, servers, and data storage equipment, but also software
such as the server operating system and DBMS. It also provides security protection and remote
access mechanism. Most of the physical design issues are addressed by Windows Azure, which
provides the environment where IT professionals can focus on the development and management
of databases and applications. IT professionals who are familiar with the Windows development
environment will have no diiculty working in the Windows Azure development environment. he
database design tools, database application development software, and database management utili-
ties are about the same. IT professionals can continue to use their knowledge and skills in cloud-
based database development. Windows Azure provides a highly available development environment.
With Windows Azure, developers can work on their projects from anywhere and at any time. he
Windows Azure development environment is highly scalable. Additional database capacity can be
added as desired until the subscription limit is reached. Data may be distributed to multiple servers
