Daawarehouse Interview Questions

What is a Database?
What is OLTP?
What is a Data Warehouse?
Why we need a Data Warehouse?
Who will use Data Warehouse?
Purpose of Analysis and Reporting
Difference between Data, Information and Knowledge
Characteristics and Importance of Transaction Systems -- OLTP
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Difference type of Data Warehouse Architectures?
Simple DWH architecture
DWH architecture with staging area
DWH architecture with staging area and pre staging area
DWH architecture with staging area and pre staging area and Data Marts
Definitions of DWH
Ralph Kimball's DWH Definition
Bill Inmon's DWH Definition
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Different types of Data Warehouse
Approaches
Top down Approach
Bottom up Approach
Difference between Top down Approach and Bottom up Approach
Characteristics of DWH
Differences between OLTP system and DWH
Definition of Data Mart
Different types of Data Marts
Dependent & Independent Data Marts
Difference between Dependent Data Mart and InDependent Data Marts
Difference between Data Mart and Data Warehouse
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Data Modeling
Different type of Data Modeling's
E-R modeling
Dimensional Modelling
Different Types of Dimensional Modelling
Star Schema
Snow Falke Schema
Integrated/Galaxy Schema
What is Dimension?
What is Fact?
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Different types if dimensions based on the data changes in the dimensions
Rapidly Changed Dimension
Slowly Changed Dimension
Definition and Implementation of SCD Type 1
Definition and Implementation of SCD Type 2
Definition and Implementation of SCD Type 3
Unchanged Dimension
Importance of Surrogate Key in SCD's
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Types of Dimensions and Fact Tables
Conformed Dimension
Degenerated Dimension
Time Dimension
Types of Facts
Additive Fact
Semi Additive Fact
Factless Additive Fact
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Extraction Transformation and Loading
(ETL Process)
Different types of sources
Methods of extraction
Full Extraction and its process
Incremental/Delta Extraction and its process
Transformations
Transformations Categories
Data Cleansing
Data Scrubbing
Data Merging
Data Aggregation
Loading
Different types of loadings
Initial Loading and its process
Incremental/Delta Loading and its process