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1.

What is the difference between ER Modelling vs Dimensional Modelling?

Answer»
ER ModellingDimensional Modelling
It SUPPORTS OLTPIt supports OLAP
ER Modelling is always normalizedDimensional Modelling is always denormalized
It removes the redundancy.It permits redundancy.
This model for ORGANIZATION or enterprise is very hard for PEOPLE to VISUALIZE and keep in their headsThis model is very EASY to understand.
Discussion
2.

What is a real-time data warehouse and what are its benefits?

Answer»

A real-time DATA WAREHOUSE COLLECTS, cleanses, stores transforms, and circulates the information in real-time. BENEFITS of a real-time data warehouse:

  • Faster Decisions
  • Faster Recovery
  • No Batch Windows
  • Optimization
  • Ideal Data LOAD
Discussion
3.

What is the snowflake schema in the data warehouse?

Answer»

In the data WAREHOUSE, a snowflake SCHEMA is the variation of the star schema. It is the form of DIMENSIONAL modeling where dimensions are being stored in MULTIPLE related DIMENSION tables. It is majorly used to improve the performance of certain queries.
Discussion
4.

What are the types of dimensional modeling in data warehouses?

Answer»

In Data warehouses, there are THREE types of DIMENSIONAL modeling:

  • CONCEPTUAL Modeling
  • Physical Modeling
  • Logical Modeling
10. What is bus architecture in the data WAREHOUSE?

In the data warehouse, bus architecture is made up of the set of tightly combined data marts that gets their potential from fact tables and conformed dimensions.
Where,

1. Conformed dimensions

it is defined and IMPLEMENTED only once so that it is meant to be the same thing wherever it is being used.

2. Fact Tables:

which are conformed includes the things that derive revenue, profit, standard costs, and standard price.
Discussion
5.

What are the main differences between structured and unstructured data?

Answer»
BasisStructured DataUnstructured Data
AnalysisQuantitativeQualitative
SearchingEasy USING SQL-based approachesMay require the use of special tools
StorageIt REQUIRES more storage to accommodate defined data structures.In this, some forms require LESS storage; others have large file formats, requiring more storage.
FormatIt has a predefined format that uses ALPHANUMERIC characters.It has typically non-character-oriented digital REPRESENTATIONS.
Discussion
6.

What are the steps to build the data warehouse?

Answer»

To build the data WAREHOUSE, one needs to follow the below STEPS:

  • Gather all the business requirements.
  • Necessary sources should be identified.
  • Identify the facts.
  • DIMENSIONS should be defined.
  • ATTRIBUTES should be defined.
  • Redefine the attributes and dimensions, if they are required.
  • Organize the hierarchy of Attribute
  • Define relationships.
  • Assign UNIQUE identifiers.
Discussion
7.

Would you like to tell us the difference between Data Warehousing and Data Mining?

Answer»
DATA WarehousingData Mining
It is defined as a huge DATABASE that is designed to carry out analytical processes.It is defined as the PROCESS that determines the hidden relationships in patterns among different SETS of data.
It is used to combine huge sets of data.It determines the useful meaning and insights from large sets of data.
It can easily store large quantities of data of any organization.It is used to identify the patterns, frauds, and relationships in an organization.
Data warehousing can be performed by engineers.Data mining is performed by businessmen with the help of engineers.
Discussion
8.

What is the difference between various types of data warehousing?

Answer»
Enterprise Data WAREHOUSEOperational Data StoreData Mart
It GIVES the controlled DATABASE for decision support throughout the enterprise.Under its scope, it has a broad enterprise which is unlikely a REAL enterprise Data warehouse. In this, data gets refreshed in rare real-time and it is being used for daily business activity.It is a sub-part of the data warehouse. It is designed for particular lines of business, hence support for a particular reason.
Discussion
9.

What is data modeling in the data warehouse?

Answer»

It DEMONSTRATES ONE of the most common ways of planning the blueprints of the DEFINITE and summed up information of the data warehouse. The objective of data warehouse modeling is to foster a diagram portraying the REALITY, or if nothing else a piece of the reality, which the data warehouse is EXPECTED to help.
Discussion
10.

Why do we need a data warehouse instead of a database?

Answer»

A data warehouse is DESIGNED to separate the analysis of BIGGER data and processes the query from the transactional processes that are focused on writing.
We opt data warehouse instead of a database because of the benefits listed below:

  • It enables historical insight.
  • Enhances the quality of Data
  • Boost the efficiency
  • Drives the revenue
  • It increases the speed of data analytics
  • It PROVIDES data security
  • It has very much higher query performance and insights
2. Which database is best for the data warehouses?

Relational database (RDBMS). This database allows you to store detailed, consolidated, and company-wide data. It is based out on the DESIGN of “Star schema” and it is established by the various data marts that are integrated through dimensions and confirmed facts.
However, the best database software for the data warehouses will DEPEND on your requirements.
Discussion