The Advantages of Parallel Databases
Organizations of every size benefit from databases because they improve the management of information. The database has a server, a specialized program that oversees all user requests for data and adheres to strict rules for security and system integrity. If an organization has a large user base and millions of records to process, it may turn to a parallel database approach. Parallel databases are fast, flexible and reliable.
A typical database resides on a dedicated computer connected to others on a data network. The server program, running on the computer, handles user requests for data. As more people try to access the database, however, the server becomes overwhelmed. Upgrading to a faster computer helps, but only to a point. A parallel database solves this problem by splitting database operations into separate tasks, each running on a separate computer. The computers share the workload, allowing more database processing than is possible with a single server.
The main advantage to parallel databases is speed. The server breaks up a user database request into parts and dispatches each part to a separate computer. They work on the parts simultaneously and merge the results, passing them back to the user. This speeds up most data requests, allowing faster access to very large databases.
A parallel database, properly configured, can continue to work despite the failure of any computer in the cluster. The database server senses that a specific computer is not responding and reroutes its work to the remaining computers. Some organizations, such as Web retailers, want as close to around-the-clock availability as possible for their database; a parallel database maintains high reliability. This approach also helps when the computer technicians perform scheduled maintenance on a computer. They send a command to the server to take the affected computer out of service, then perform the necessary maintenance and upgrades. When they are finished, they put the computer back into service. The database remains available throughout the process.
As more users request access to the database, the computer administrators add more computers to the parallel server, boosting its overall capacity. A parallel database, for example, allows a large online retailer to have thousands of users accessing information at the same time. This level of performance is not possible with a single server.