Data Warehousing - What is data cleaning? How can we do that?

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What is data cleaning? How can we do that?

Total Answers and Comments: 5

Last Update: July 09, 2007 Asked by: GeekAdmin

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Submitted by: Hakoonamatata

Data cleaning is a self explainatory term. Most of the data warehouses in the world source data from multiple systems - systems that were created long before data warehousing was well understood, and hence without the vision to consolidate the same in a single repository of information. In such a scenario, the possiblities of the following are there:
1. Missing information for a column from one of the data sources;
2. Inconsistent information among different data sources;
3. Orphan records;
4. Outliar data points;
5. Different data types for the same information among various data sources, leading to improper conversion;
6. Data breaching business rules

In order to ensure that the data warehouse is not infected by any of these discrepencies, it is important to cleanse the data using a set of business rules, before it makes its way into the data warehouse.

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

October 06, 2006 05:28:06

srinivas vadlakonda

RE: What is data cleaning? How can we do that?

clearning means cleaning the data like filtering and merging before loading the data into datawarehouse

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October 25, 2006 11:32:37

jessa

RE: What is data cleaning? How can we do that?

data cleaning is removing discrepencies from the record like removing duplication redundancy etc..in short making the data as relevant as can be made for the ultimate purpose of business analysis

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February 10, 2007 05:16:24

jyothi

RE: What is data cleaning? How can we do that?

Data Cleaning is a process of avoiding the unnecessary information in the process of data maintainance. Data Cleaning can be done by using clustering

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March 02, 2007 08:36:03

chinnodu

RE: What is data cleaning? How can we do that?

It is a process of identifying and changing the inconsistencies and inaquerecies

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July 09, 2007 10:34:14

Hakoonamatata

Member Since: July 2007 Contribution: 5

RE: What is data cleaning? How can we do that?

Data cleaning is a self explainatory term. Most of the data warehouses in the world source data from multiple systems - systems that were created long before data warehousing was well understood and hence without the vision to consolidate the same in a single repository of information. In such a scenario the possiblities of the following are there:
1. Missing information for a column from one of the data sources;
2. Inconsistent information among different data sources;
3. Orphan records;
4. Outliar data points;
5. Different data types for the same information among various data sources leading to improper conversion;
6. Data breaching business rules

In order to ensure that the data warehouse is not infected by any of these discrepencies it is important to cleanse the data using a set of business rules before it makes its way into the data warehouse.

Is this answer useful? Yes | No

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