Oracle Database Architecture
An Oracle database is a collection of data treated as unit. The purpose of a database is to store and retrieve related information. A database server is the key to solving the problems of information management. In general, a server reliably manages a large amount of data in a multiuser environment so that many users can concurrently access the same data. All this is accomplished while delivering high performance. A database server also prevents unauthorized access and provides efficient solutions for failure recovery.
Oracle Database is the first database designed for enterprise grid computing, the most flexible and cost effective way to manage information and applications. Enterprise grid computing creates large pools of industry-standard, modular storage and servers. With this architecture, each new system can be rapidly provisioned from the pool of components. There is no need for peak workloads, because capacity can be easily added or reallocated from the resource pools as needed.
The database has logical structures and physical structures. Because the physical and logical structures are separate, the physical storage of data can be managed without affection the access to logical storage structures.
Overview of Oracle Grid Architecture
Grid computing is a new IT architecture that produces more resilient and lower cost enterprise information systems. With grid computing, groups of independent, modular hardware and software components can be connected and rejoined on demand to meet the changing needs of buinesses.
Benefits of Grid Computing Compared to other models of computing, IT systems designed and implemented in the grid style deliver higher qualify of service, lower cost, and greater flexibility. Higher qualify of service results from having no single point of failure, a robust security infrastructure, and centralized, policy-driven management. Lower costs derive from increasing the utilization of resources and dramatically reducing management and maintenance costs. Rather than dedicating a stack of software and hardware to a specific task, all resources are pooled and allocated on demand, thus eliminating under utilized capacity and redundant capabilities. Grid computing also enables the use of smaller individual hardware components, thus reducing the cost of each individual component and providing more flexibility to devote resources in accordance with changing needs.
Grid Computing Defined The grid style of computing treats collections of similar IT resources holistically as a single pool, while exploiting the distinct nature of individual resources within the pool. To address simultaneously the problems of monolithic systems and fragmented resources, grid computing achieves a balance between the benefits of holistic resource management and flexible independent resource control. IT resources managed in a grid include:
-Infrastructure: the hardware and software that create a data storage and program execution environment
-Applications:the program logic and flow that define specific business processes
-Information: the meanings inherent in all different types of data used to conduct business
Core Tenets of Grid Computing Two core tenets uniquely distinguish grid computing from other styles of computing, such as mainframe, client-server, or multi-tier: virtualization and provisioning.
Grid Computing in Oracle Database 10g
Infrastructure Grid
- Server Virtualization. Oracle Real Application Clusters 10G(RAC) enable a single database to run across multiple clustered nodes in a grid, pooling the processing resources of serveral standard machines. Oracle is uniquely flexible in its ability to provision workload across machines because it is the only database technology that does not require data to be partitioned and distributed along with the work. Oracle 10g Release 2 software includes enhancements for balancing connections across RAC instances, based on policies.
- Storage Virtualization. The oracle Automatic Storage Management(ASM) feature of Oracle Database 10g provides a virtualization layer between the database and storage so that multiple disks can be treated as a single disk group and disks can be dynamically added or removed while keeping databases online. Existing data will automatically be spread across available disks for performance and utiliaztion optimiaztion. In Oracle 10g Release 2, ASM supports multiple databases, which could be at different software version levels, accessing the same storage pool.
-Grid Management. Because grid computing pools together multiple servers and disks and allocates them to multiple purposes, it becomes more important that individual resources are largely self-managing and that other management functions are centralized.
The Grid Control feature of Oracle Enterprise Manager 10g provides a single console to manage multiple systems together as a logical group. Grid control manages provisioning of nodes in the grid with the appropriate full stack of software and enables configurations and security settings to be maintained centrally for groups of systems. Another aspect to grid management is managing user identities in a way that is both highly secure and easy to maintain.
Applications Grid - Standard Web Services Support. In addition to the robust web services support in Oracle Application Server 10g, Oracle database 10g can publish and consume web services. DML and DDL operations can be exposed as web services, and functions within the database can make a web service appear as a SQL row source, enabling use of powerful SQL tools to analyze web service data in conjunction with relational and non-relational data.
Information Grid
- Data Provisioning.
- Centralized Data Management.
- Metadata Management.
- Metadata Inference.