VSAM Vs DB2 (for Experienced)
The differences are written by considering VSAM and DB2 are as below -
- VSAM files can be ESDS, KSDS, LDS, or RRDS.
- DB2 is the database system that uses Relational DataBase Management System (RDBMS).
|VSAM is the file access method.||DB2 is the DataBase Management System.|
|VSAM files can only access in the mainframe environment.||DB2 is accessed by multiple languages from different platforms, including Windows, HP-UX, Sun Solaris, Unix, AIX, Linux, AS/400, and OS/390.|
|Changing the VSAM file structure is complex once defined.||DB2 structure can change quickly when requirements changed.|
|Have no or little support for security and integrity issues.||Have full support for security and integrity issues.|
|Have no or little support for recovery and concurrency issues.||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 the workstation (local system) to the mainframe.|
|The access method is used to perform the activities.||Supports a rich suite of tools/products for administration, management, data manipulation, data replication.|
|VSAM doesn't support any technology except the mainframe.||DB2 is web-enabled with built-in Java support.|
|Provides much less data independence.||Provides more data independence.|
|Have no true data dictionary concept.||Have data dictionary concept.|
|Taking backup needs time and exclusive control on the file.||Can take backup easily.|
|Stored records internal structure is not aware and can't handle the request that relies on the knowledge of structure.||Data storage structure is known and informed when created and can handle the request that relies on the knowledge of structure. Example - Get the maximum salary.|
|Backout, specific data management changes, is not possible because VSAM won't track the changes.||Backing out specific data management changes is possible.|
To conclude this, DB2 is a more effective and far better option than using VSAM files. However, DB2 can handle large volumes of data and can be accessed from multiple platforms. DB2 replaces the VSAM files everywhere except where the processing data size is small.
If the processing data size is small and needs more processing speed, VSAM is a better option than DB2.