Which DB access method (OSAM or VSAM) is better and why?
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Answer / s
OSAM is better because with even block sizes you can have a
maximum size of 8 GB for a dataset. OSAM supports
sequential buffering, reads 10 consecutive blocks with one
1 I/O operation. This will reduce the elapsed time by 50%.
It also supports queued writes which also results CPU and
elapsed time savings.
| Is This Answer Correct ? | 9 Yes | 0 No |
Answer / john i harper
With IMS HALDBs, OSAM or VSAM can go to 40 terabytes, so
size is no longer a problem. However, OSAM was written by
IMS to do one thing, hold IMS data securely, and move it
quickly. VSAM was written to do many things, making the code
path longer. That increases the time needed to run, and
presents
a greater risk of failure.
Finally, OSAM is written and owned by IMS, so you only have
to ask one development team instead of two if you want any
new features added.
| Is This Answer Correct ? | 3 Yes | 0 No |
Answer / azharuddin khan
Hi Osam is better becoz we can extend upto 8GB in OSAM
whereas in VSAM its only 4GB.
| Is This Answer Correct ? | 2 Yes | 1 No |
Answer / rajasekhar
vsam
later i will give the clear information abt this.
| Is This Answer Correct ? | 2 Yes | 2 No |
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