Have full support for recovery and concurrency issues. Handles large volumes of data, but the accessing speed is low. Handles large volumes of data without reducing accessing speed. Have less data management. So the data analysis can't be improved if it has large volumes of data. Have better data management by interacting with batch, online, and other data exchanging activities. So the deeper and improved data analysis can be performed. Licenses and maintenance costs are more.
Licenses and maintenance costs are less. Low-level scalable. Provides a high level of scalability, extending from workstation local system to mainframe. In fact, the DBMS is typically built on top of some kind of file manager. Thus, the user of a file management systems will be able to create and destroy stored files and perform simple retrieval and update operations on stored records in such files. Since then, DB2 has come a long way and provides facilities to exploit the latest hardware and software technologies, accommodating a majority of user requirements.
The ability to manage many concurrent users, very large databases, high transaction rates and deliver consistent rapid response is fundamental and delivered by DB2 through the wide range of platforms and the exploitation of platform-specific features. Beyond this, DB2 meets the requirements for high availability, low planned maintenance, wide connectivity, open standards and effective manageability.
It was initially released by IBM in and is part of the Base product. VSAM provides a number of data set types or data organization schemes. RLS itself does not provide transactional recovery.
VSAM is tightly coupled with the mainframe and hence has a restricted choice of platform. With DB2, as the business process changes, modifying the database such as adding or removing columns is possible.
Referential integrity of data across tables is taken care of by DB2 itself. Cost of maintenance of VSAM applications is more since even inserting or deleting a field at a later stage is difficult. DB2 provides a high degree of security in the sense that the unit of data that can be individually protected ranges all the way from an entire table to a specific data value at a specific row-and-column position.
Different users can have different privileges on the same object. The view mechanism can be used to hide sensitive data from unauthorized users. DB2 maintains referential integrity based on the rules specified by the application developer.
IBM's DataLinks technology manages the integrity of externally stored data even when maintained by external applications. In case of VSAM, maintaining referential integrity becomes the application developers' responsibility. DB2 also delivers significant query and client interface functions such as Net. DB2 can handle unlimited data.
Better concurrency support is achieved by using row-level locking. It does not provide the functions that are required to enable multiple users to update a shared data set with complete integrity. DB2 is web-enabled with built in Java support. Products like Net. Data, Web forms, Web Focus provide rapid building of Web applications. Very strong, language independent, stored procedure support including support for Java allows business logic to be shared across all architectures.
Thus you open the world of DB2 directly to the web for any application and usage. Generally VSAM data is accessible only by local applications and accessed via terminals only. For accessing VSAM from systems other than mainframe, custom interfaces needs to be built making it both an expensive and difficult option.
Being a DBMS available on various platforms, DB2 promotes a distributed, wholly interconnected distribution environment e. The built-in Data Propagator enables data distribution, data replication and workload distribution. Update-anywhere replication is a standard feature of DB2. Existing skills can be deployed and utilized throughout the enterprise thus maximizing ROI and with fewer individuals. VSAM is a file access method. DBMS provides a central store of data that can be accessed by multiple users, from multiple locations.
Flat files are designed to access by single user at a time. With DBMS, systems can be modified much more easily when business requirements change. New categories of data can be added to the database without disruption to the existing system. Performing a similar task in VSAM is much more difficult especially if the file does not have any unused filler area at the end. Share this:.
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