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What for we use Hashed files in datastage job? Give an example
noverino
- Feb 23rd, 2007
I'm agree with naveen patil, Hashed file is used for lookup process. Beside that, Hashed file can also be used if we want to get Distinct data from a source by using the column as key. Sample, I w...
naveen patil
- Nov 28th, 2006
Mainly hased files are used for lookup perpose. for example ur looking for the data whether the entry is their or not. if it is thr do something otherwise something else
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What are different types of file formats??
PRASHANT NARAYANI
- Dec 26th, 2006
.csv files. dxs files( standard extension of data stage)
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Why is hash file is faster than sequential file n odbc stage??
aladap12
- Jun 28th, 2009
Hash file is datastage internal file. Data will be stored on computer memory..and works on key column. So retrieval will be faster when compare to hitting the database.
Lavanya
- Nov 8th, 2006
Hash file is indexed. Also it works under hashing algo. That's why the search is faster in hash file.
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How can we improve performance in aggregator stage??
prav2000
- Dec 21st, 2006
Select the most appropriate partitioning method based on the data analysis. Hash partitoning performs well in most of the cases.
BALU
- Dec 4th, 2006
For improving the performance when you use aggregator stage sort the data before u pass pass to the aggregator stage.
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How to enable the runtime column propagation in the datastage?Where does this option exists?
nagoosk
- May 29th, 2008
It is available in 3 places1)When u open the ds Administrator ; there open any project properties;there u can see the Runtime Column Propagation.2) If u open the job properties there u can see th...
sarita
- Dec 11th, 2006
There is an option in data stage administrator->projects tab->properties button->general tab-> enable runtime column propogation for parallel jobs. If you enable this, you can select runti...
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What is a sequential file that has single input link??
veer.dwh
- Sep 28th, 2009
Sequntial file stage supports either one input link or one output link.it runs sequntially(like row by row process), if it is reading single input file and won't support any parallism.it runs parallely, if it is reading multiple files and will support parallism techniques.
Raghu
- Aug 1st, 2007
Sequential file always has?single link because its it cannot accept the multiple links or threads.Data in sequential file always runs sequentially..HTHRaghu Mule
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What are different types of star schema??
veer.dwh
- Sep 28th, 2009
There are 2 types of star schemas in datastage1.Starschema: A single fact table sits in middele and surounded dimension tables radically connect with fact table like a star. in star schema dimension t...
PRASHANT NARAYANI
- Dec 27th, 2006
Multi star schema or galaxy schema is one of the type of star schema
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sample:
Cola Colb Colc
1 10 100
2 20 200
3 30 300
Assume: cola is primary key
How will you fetch the record with maximum cola value using data stage tool into the target system">Suppose you have table "sample" & three columns in that tablesample:Cola Colb Colc1 10 1002 20 2003 30 300Assume: cola is primary keyHow will you fetch the record with maximum cola value using data stage tool into the target system
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How to run a job using Command line?
nikhilanshuman
- Dec 25th, 2009
The command is "dsjob" and case sensitive.Following is the command :dsjob -run -wait -warn 999 -jobstatus -project name -job name
sai
- Mar 31st, 2007
Dsjobs-run-jobstatus projectname jobname/filename
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If i run the job first 10 times there is no time variation in job execution.In same way i run the job for 100 times it takes 10 times extra time.what is the solution for it?
nikhilanshuman
- Mar 19th, 2010
The solution is to check for any bottlenecks. Try running the job for two or three more times after certain intervals and take performance statistics. If the performace is still slow then try optimizing the jobs.
nikhilanshuman
- Mar 19th, 2010
Depends on the runtime environment. Sometimes on the datastage server many processes are running at the same time. Sometimes the server might be lacking enough resources required for the job. Th...
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What is the use and advantage of procedure in datastage?
hemant.agarwal03
- Nov 13th, 2009
If we have a complex business logic and we may need to create mutiple jobs to achive that , then we use procedure in data stage which provide us final output in a single job. It is faster then normal SQL statement also.
Him121
- Jun 22nd, 2007
To trigger Database operations at before or after DB stage access.
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How do we use Job Parameters in datastage jobs.
I know we use them in the project level and also in the job level and also that we can give values at run time(like UN, Pswd etc). Theoratically I understood. But practically unable to implement it. Can somebody explain me in detail with an example. I wud seriously appreciate your help. Thanks Guyz.
Behrouz
- Jan 27th, 2009
For example I create a parameter for my hashfile folder like it : Name: $pHashdir, type:string,def.value: C:DataStageInput DATAHash and when I use my hash file in path file name i use just ...
Fanguna
- Nov 19th, 2007
There is an icon to go to Job parameters in the tool bar. Or you can press Ctrl+J to enter into Job Parameters dialog box. Once you enter, give a parameter name and corresponding default value for it....
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What is surrogate key? what is routine and explain the use in datastage parallel server jobs?
nikhilanshuman
- Nov 30th, 2010
A surrogate key is none business key. it can be a sequential number with no business meanings. these are useful for the underlying applications to maintain relationships between tables.Routines are th...
pavan.daddanalla
- Apr 14th, 2008
Surrogate key is a separate key column which is generated by surrogate key generator. routines are nothing but subset of functions
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