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In real time scenario where update strategy transformation is used?if we dml operations in session properties then what is the use of update strategy transforamtion ?

  
Total Answers and Comments: 2 Last Update: February 22, 2007     Asked by: narendranathyogi 
  
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August 29, 2006 03:09:13   #1  
Rangini vignesh        
RE: In real time scenario where update strategy transf...

Ans:We can use Update strategy transformation in two ways .

1.Mapping level.

2.session level.

Importence of Update strategy transformation in both cases as follows.

In real time if we want to update the existing record with the same source data you can go for session level update logic.

If you want to applay different set of rules for updating or inserting a record,even that record is existed in the warehouse table .you can go for mapping level Update strategy transformation.It means that if you are using Router transformation for performaning different activities.

EX: If the employee 'X1234 ' is getting Bonus then updating the Allowance with 10% less.If not, inserting the record with new Bonus in the Warehouse table.


 
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February 22, 2007 02:18:13   #2  
Noel Lastra Member Since: February 2007   Contribution: 38    
RE: In real time scenario where update strategy transf...
Update strategy, Supposed you have a router you are router has 3 groups, 1 group is for update, 1 group is for delete, 1 group is for insert to target table.  You can use the update strategy for each group before going to target and changing the expression to DD_UPDATE, DD_DELETE, and DD_Insert.  Don't forget to change the session property, treat source rows as (something like this) DATA_DRIVEN.
 
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Read Answers (3) | Asked by : asha
In real time scenario where update strategy transformation is used?if we dml operations in session properties then what is the use of update strategy transforamtion ?
How you capture changes in data if the source system does not have option of storing date/time field in source table from where you need to extract the data?
The DW database can be Oracle or Teradata. The requirement here is to pull data from source system and ETL need to device a mechanism to identify the changes or new records. The source system can be a 
Read Answers (1) | Asked by : GeekNo1
Latest Answer : Update strategy transformation determines whether to insert, update, delete or reject a record for the target.  We can bypass update strategy transformation by creating a router to divide rows based on insert, update, etc and connecting ...
Latest Answer : When the DB servers are different say for ex one is oracle and other SQL server, we cant pull th data at DB level. ...
In What scenario ETL coding is preferred than Database level SQL, PL/SQL coding? What is the methodology and process followed for ETL testing in Data warehouse environment? Develop a mapping to extract the employee drawing maximum salary where deptno = department drawing... If LKP on target table is taken, can we update the rows without update strategy transformation? How you capture changes in data if the source system does not have option of storing date/time field... What is the Difference between
Read Answers (1) | Asked by : srihari

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