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What are the various methods of getting incremental records or delta records from the source systems?

  
Total Answers and Comments: 6 Last Update: December 11, 2007   
  
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May 21, 2005 15:37:17   #1  
sapna        

RE: What are the various methods of getting incremental records or delta records from the source systems...
getting incremental records from source systems to target can be done 
by using incremental aggregation transformation

 
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July 20, 2005 07:23:18   #2  
Kesavan,H.        

RE: What are the various methods of getting incremental records or delta records from the source systems...
One foolproof method is to maintain a field called 'Last Extraction Date' and then impose a condition in the code saying 'current_extraction_date > last_extraction_date'.
 
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August 12, 2005 01:47:26   #3  
veepee        

RE: What are the various methods of getting incremental records or delta records from the source systems...
Here is an Oracle specific technique- 
Its called Change Data Capture 
 
http://www.databasejournal.com/features/oracle/article.php/1588261 
 
hope this helps 

 
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May 06, 2006 00:38:15   #4  
shaik        

RE: What are the various methods of getting incrementa...

Using mapping parameters and variable or type1 we can easily define from where parameter will  start and how variable will change as deltas will get from OLTP systems


 
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August 14, 2007 04:24:07   #5  
Are Ramakrishna Rao        

RE: What are the various methods of getting incrementa...
Above solution will not be helpful in case of late arrivel fact and late arrivel dimentional records. Generall in any data source we will have transaction date ( when the transaction happened) and load date ( when the data loaded in source ) for numerical measure data similarly  Ener date ( when the details are provided by the cutomer ) load date for dimentional data . we have to use both the date stamps to retrive the data from the data sources. 
 
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December 11, 2007 06:42:07   #6  
noushadn Member Since: December 2007   Contribution: 1    

RE: What are the various methods of getting incremental records or delta records from the source systems?

We can use control table update and ipf files for capturing incremental data or delta data from a source. Control table will maintain the details like from which timestamp (previous) to which timestamp (current) we have taken the data.
If the session is taking data everyday (daily run) then the delta will be of one day. Previous timestamp will be of yesterday's date (P1) and current timestamp will be the time (C1)of run of the job. So in today’s run we will get one day data.
Next day when job runs C1 will become P2 and today’s run time will become C2, so we will not miss any records incremented i the source systems. This will go on.
Incase on weekly runs the delta will be of one week.
Let me know if you need any further information.


 
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