Hi,
I am new to datastage, i need some sample dynamic and static hashfile samples.
if possible please send it to my mailid shrivaths@gmail.com
Thanks in advance
Hash file in Datastage
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Hash file in Datastage
Shrivaths
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There's no such thing. By the way, the correct term is "hashed" file. A hashed file is a database table. Asking for a sample of a hashed file is like asking for a sample of an Oracle or DB2 table. It's just not going to happen.
There are both dynamic and static hashed files in each project directory. VOCLIB and SYS.MESSAGE are examples of static hashed files. Most of the other tables, like DS_JOBS, are dynamic.
The difference is that a dynamic hashed file can manage its table space automatically based on the volume of data requiring to be stored, while a static hashed file can only be reorganized with manual intervention. But, when the volume of data is unchanging, such as in the SYS.MESSAGE table, well-tuned static hashed files offer certain advantages in access times. If the volume of data is changing, however, static hashed files need to be monitored and, possibly, re-tuned periodically.
There are both dynamic and static hashed files in each project directory. VOCLIB and SYS.MESSAGE are examples of static hashed files. Most of the other tables, like DS_JOBS, are dynamic.
The difference is that a dynamic hashed file can manage its table space automatically based on the volume of data requiring to be stored, while a static hashed file can only be reorganized with manual intervention. But, when the volume of data is unchanging, such as in the SYS.MESSAGE table, well-tuned static hashed files offer certain advantages in access times. If the volume of data is changing, however, static hashed files need to be monitored and, possibly, re-tuned periodically.
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Any contribution to this forum is my own opinion and does not necessarily reflect any position that IBM may hold.
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Better than what? What really is your question?
Hashed files are brilliant for key equality lookups because a key can be found with a single logical I/O irrespective of the number of keys in the table. No table scan, no index scan, no index even.
Hashed files are brilliant for key equality lookups because a key can be found with a single logical I/O irrespective of the number of keys in the table. No table scan, no index scan, no index even.
Last edited by ray.wurlod on Fri Sep 26, 2008 4:52 am, edited 1 time in total.
IBM Software Services Group
Any contribution to this forum is my own opinion and does not necessarily reflect any position that IBM may hold.
Any contribution to this forum is my own opinion and does not necessarily reflect any position that IBM may hold.
Hey , I think you are trying to create a new Hashed file and practice.
For this you have to go through document's and try it out. Incase you have any errors or problems post in Dsxchange , then we can help you.
But no one can send you any hashed file through mail. you must read more on stages and jobs. jobs can be exported and moved, but stages can't be moved or exported.
Any way search in Google, people are lucky to get full job which uses major stages. import in your datastage environment and try it out. You may be lucky
For this you have to go through document's and try it out. Incase you have any errors or problems post in Dsxchange , then we can help you.
But no one can send you any hashed file through mail. you must read more on stages and jobs. jobs can be exported and moved, but stages can't be moved or exported.
Any way search in Google, people are lucky to get full job which uses major stages. import in your datastage environment and try it out. You may be lucky
Thanks, BK
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