ETL - Extract / Transform Process

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Extract / Transform Process

Describe the stages of extract / transform process, including what should happen at each stage and in what order?

Total Answers and Comments: 4

Last Update: August 19, 2009 Asked by: riyazz.shaik

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Submitted by: tisha24

Extraction means getting data from different/single source and loading into the staging database, in other words brining the data from different sources (like databases or flat diles) into the datastage(or any ETL tool) for further processing.

In the extraction we will ensure the nullability and cleansing the data.

Transformation: where we have to implement the following:

1.the business logics to the necessary fields,
2.populate the primary and foreign keys,
3.aggrecation of data.
4.Data conversion if necessary
5.implmentation of SCD's

Above answer was rated as good by the following members:
senthamizharasu

October 14, 2008 15:52:16

Mamta11

Member Since: July 2008 Contribution: 12

RE: Extract / Transform Process

In the Extract process all the data from source system (relationaltables or flat files or XML sources) is extracted and saved onto the stagging area.

All the data from Staggign area will be transformed applying the business logic.

All the transformed data will be loaded to the target.

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December 18, 2008 07:07:26

tisha24

Member Since: September 2008 Contribution: 10

RE: Extract / Transform Process

Extraction means getting data from different/single source and loading into the staging database in other words brining the data from different sources (like databases or flat diles) into the datastage(or any ETL tool) for further processing.

In the extraction we will ensure the nullability and cleansing the data.

Transformation: where we have to implement the following:

1.the business logics to the necessary fields
2.populate the primary and foreign keys
3.aggrecation of data.
4.Data conversion if necessary
5.implmentation of SCD's

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Overall Rating: +1

May 20, 2009 00:53:07

smsreddy

Member Since: May 2009 Contribution: 5

RE: Extract / Transform Process

Generally this is going to be 2 stage process some times 3 stage depends on the requirement.
Most of the time its 2 stage process. In first phase is to extract data from different source systems for eg : Oracle Flat Files SAP etc. and load into Stage area as it is and in 2nd stage apply transformation/business rules and load from Stage area to Datawarehouse/mart.

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August 19, 2009 02:20:38

sagarw9

Member Since: August 2009 Contribution: 1

RE: Extract / Transform Process

In the extract process we extract the data from the different sources like data files flat files etc.. into the stagging area or we can say input area for the further processing.
Once get files in the input data is applied for the processing by applying some business logics to meet the requirements.
After processing data it is loaded into the target locations.

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