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Mimic Diagram
What is meant by mimic diagram? Where it is used?
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Multi-Valued Dimension
Illustrate one detailed example for multi-valued dimension or bridge table?
ramanapaidi
- Jul 1st, 2009
Health care bill has line item of diagnosis, for which there could be multiple values
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Use of ROLLUP and CUBE
What is a use of ROLLUP and CUBE in ORACLE? How do they help Data Warehousing applications?
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Reconcialation Process
What is the Reconcialation Process?
v_madhu29
- Aug 11th, 2009
Reconcilation process is a systematic comparision between the data in Dataware house and data in source system.The comparision may be a set a predefined summary values or detailed data periodically.
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Data Warehouse as Transaction Database
Can a Data Warehouse also be used for Transaction Database? If Yes Why, If No Why not?
sixto.dsilva
- Aug 15th, 2009
As the definaton of Datawarehouse say it is repository of historial data which is used by Busines users to run some reports on his/her area of interests.Data is not loaded everyhour or every mtes in D...
SQLGal
- Jun 7th, 2009
No, a data warehouse cannot by definition be used as a transaction database. A data warehouse is "read only" data that does not change once it has been loaded and used for informa...
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Lookup Performance
How does the usage of Dataset improve the performance during lookups?
sixto.dsilva
- Aug 17th, 2009
Correct me if i misunderstood your question. I think you want to know whether the usage data will improve the graph performance. I think definitely the usage of data will definitely improve the graph ...
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ETL Load Frequency and Load Window
What is Load Frequency and Load Window in ETL?
zann1
- Sep 7th, 2009
ETL Load frequency is how often the ETL processes (that load data into the data warehouse) are run.Load Window is the time allocated for ETL load to execute.e.g. If the load is run daily, and the time allowed for execution is 8 hours then:ETL load frequency = dailyLoad window = 8 hours
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If you source data from a system that you (warehouse team) have no authority to enforce data quality at the source level, how do you handle this? Do you apply data validation just after you stage the data? Or do you enforce it at the “end” of the flow (typically as you’re pushing it into the data mart)? Or do you not enforce validation at all?
Dominique
- Sep 10th, 2009
A DW is no longer relevant when it contains inconsistent data. The strength of a DW - and its robustness - also relies on the validation processes... The sooner you can detect and report any inconsist...
Nitin
- Mar 17th, 2007
One of the main purpose of Datawarehousing is to get Cleanse data.So skipping data validatons is not a good idea.It will be better to bring the data to a staging area and perform validations.Or while pushing data from the source we can perform data validations.
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SCD types and usages
What are the SCD types and what are its Usage?
pradeep16
- Oct 21st, 2009
SCD - Slowly Changing Dimensions. SCD usages in data warehouse are to store the history of transactions on dimensions. There are three types SCDs: Type1 - Just rewrite the record if there is a change...
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What is the application of data mining tools?
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Data Mart Data
Is data, transient or periodic in data mart? Explain
ashishsinha.dummy
- Nov 10th, 2009
Data marts are part of OLAP system. Data in datamarts cannot be trasient. Data will be updated in datamarts on a periodic or daily basis depending on the design of the data warehouse.-Ashish
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OOAD Object Oriented Analysis & Design
When is the need to do OOAD (Object oriented analysis & design)
subang
- Jan 17th, 2010
We use OOAD in order to design the system when overall requirements needed for developing the new system are clearly understood by the developer.
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What is data cleaning? How can we do that?
sub_guha
- Jan 25th, 2010
Data cleaning, technically called "Data Cleansing"is a group of methods for making data more reliable and accurate. Usually companies store data in warehouses so they can make meaning out of...
Hakoonamatata
- Jul 9th, 2007
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 ...
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ETL testing
How can we do the ETL testing on Data WareHouse?
anita_09
- Sep 10th, 2009
ETL testing validates that data is transformed correctly from OLTP to data warehouse. Validating the data transformed includes following main verification points: Ensures that all expected...
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Staging and Operational Data Store
What are Staging and Operational Data Stores and what is their difference?
Why does one need staging and why does one need ODS? What will happen if they are not there? Who and how is it decided that a staging or ODS is needed? Which comes first staging or ODS?jryan999
- Feb 3rd, 2010
An Operational Data Store (ODS) is a repository of active "operational" data. It's typically used to hold data for a short period (eg. Days or weeks at most), to help the business ...
srilu1234
- Jan 19th, 2010
Stagining and operational data store are different databases.It can be one database aswell to reduce the cost to maitain two databases.Staging is the place where cleansing is done and Operational Stor...
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Information Gain Concept
How to remove a particular attribute from table using the information gain concept?
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What is the difference between database and data warehousing?What is the main advantages of data warehousingWhat is mean by data stageWhat is the famous tools used for data warehousing?What is the architecture of data warehouisng model?
brahmiii
- Feb 28th, 2010
Database is the root of any data releted operations where as datawarehousing is a schema or process how effectively we access or utilize a database. Datawarehousing follows the star schema and snowflake schema as its basic schemas and we two other schemas also which are not much important.
sap_23
- Sep 3rd, 2009
Database: A database is used to record, retrieve, update business transactions which are occurred daily in business life. Data ware House: A data warehouse is used to record historical data, purely for analysis purpose for top management.
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Merge Dimension
What is the merge dimension?
Nicolas
- Apr 17th, 2010
Merge dimension is the action in Web Intelligence XI that allows to synchronize two or more data providers through common dimension. Once created, the merged dimension can be used as an object for rep...
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AutoSys Jobs Schedule
How can we schedule our jobs in third party tool - AutoSys?
saigarneni
- May 18th, 2010
We need to write shell script to run the job and write JIL on autosys to schedule the job
varghesebinu
- Dec 10th, 2009
Autosys is a total job scheduling solution that allows you to define the event dependencies, time schedules alerts etc making it a complete data center automation tool. An AutoSys job is any single co...
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What is the main difference between star and snowflake star schema? Which one is better and why?
bcsandip
- May 25th, 2010
Star Schema: 1. Dimension tables directly connected to Fact Table2. Contain de-normalized data3. Data modifications are very easily4. Highest flexibility5. Best performance6. Takes more memory space t...
geetu rani
- Mar 27th, 2008
STAR SCHEMA HAS fact table linked with dimension table directlywhile in snow flake schema the dimension tables can have futher hierarchies between them .it means in snow flake schema the tables are no...
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