DWH BASICS Interview Questions

What is Dimensional Modelling

Latest Answer: It is logical design techniques and visual techinques it

can be contain aggregate table, dimension table, fact table ...

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What is the Difference between OLTP and OLAP

Answered by swetha on 2005-03-30 12:00:33: OLTP Current

data Short database transactions Online

update/insert/delete Normalization is promoted High volume

transactions Transaction

Latest Answer: Thanks Jyothsna....... ...

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What is surrogate key ? where we use it expalin with examples

don't know

Latest Answer: We can say "Surrogate key" is a User defined primary

key.. ...

Read Answers (14) | Asked by : Minish Cherian


What are Data Marts

Data Mart is a segment of a data warehouse that can provide

data for reporting and analysis on a section, unit, department or

operation in the company, e.g. sales, payroll, production. Data

marts are sometimes

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Latest Answer: A Data Mart is the subset of the data warehouse that

caters the needs of a specific functional domain.examples of

functional domains can be given as Sales, Finance, Maketing, HR

etc. ...

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What are the methodologies of Data Warehousing.

Latest Answer: There are four methods in which one can build a

datawarehouse.1. Top-Down (Emphasizes the DW. )2. Bottom-Up

(Emphasizes data marts.)3. Hybrid (Emphasizes DW and data

marts; blends “top-down” and “bottom-up” methods.)4.

Federated (Emphasizes the need to ...

Read Answers (13) | Asked by : Srinu


What is a Data Warehousing?

Data Warehouse is a repository of integrated information,

available for queries and analysis. Data and information are

extracted from heterogeneous sources as they are

generated....This makes it much

Latest Answer: Data Warehousing is Relational Database which is

specially designed for analysis processing rather then for

querying and transactional processing. ...

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What are the vaious ETL tools in the Market
















Latest Answer: By far, the best ETL tool on the market is

Hummingbird Genio.Hummingbird is a division of OpenText, they

make, among other things, connectivity and ETL software. ...

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What is Fact table

Answer posted by Chintan on 2005-05-22 18:46:03: A table in a

data warehouse whose entries describe data in a fact table.

Dimension tables contain the data from which dimensions are

created.

Latest Answer: Fact table is the one which contains measures of

interest at most granular level.These values are numeric.Ex:sales

amount would be a measure .Each dimension table has a single-

part primary which exactly corresponds to one of the components

ofÂ multiparty ...

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What is ODS

Latest Answer: ODS means Operational Data store. ODS & Staging

layer are the two layers between the source and the target

datbases in the data warehouse..ODS is used to store the recent

data. ...

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What are conformed dimensions














Latest Answer: A dimension whichÂ can be shared with multiple fact

tables such dimensions are know as conformed dimension. ...

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What is a lookup table

Latest Answer: hi if the data is not available in the source systems

then we have to get the data by some reference tables which are

present in the database.these tables are called lookuptablesfor

example while loading the data from oltp to olap,we have ...

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What is ER Diagram

Answered by Puneet on 2005-05-07 04:21:07: ER - Stands for

entitity relationship diagrams. It is the first step in the design of

data model which will later lead to a physical database design of

possible

Latest Answer: Entity Relationship Diagrams are a major data

modelling tool and will help organize the data in your project into

entities and define the relationships There are three basic

elements in ER models: Entities are the "things" about which we

seek ...

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What is ETL





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Answered by sunitha on 2005-04-28 21:17:53: ETL is

extraction,trasformation and loading,ETL technology is used for

extraction the information from the source database and loading

it to the target database

Latest Answer: Data Acquisition technique is now called

ETL(Extraction, Transformation and Loading)Extraction-The

process of extracting the data from various sources. Sources can

be file system, database, XML file, Cobol File, ERP

etcTransformation-Transforming the ...

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What are conformed dimensions

Latest Answer: In Integrated schema Design, a dimension which can

be shared across multiple fact tables is called Conformed

Dimension. ...

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What is conformed fact?

Latest Answer: A fact,which can be used across multiple datamarts is

called as conformed fact. ...

Read Answers (8) | Asked by : narender


Can a dimension table contains numeric values?

Latest Answer: Absolutely!For example, a perishable product in a

grocery store might have SHELF_LIFE (in days) as part of the














product dimension. This value may, for example, be used to

calculate optimum inventory levels for the product. Too much

inventory, ...

Read Answers (8) | Asked by : sunil


What is a Star Schema

Answer posted by Chintan on 2005-05-22 18:34:55: A relational

database schema organized around a central table (fact table)

joined to a few smaller tables (dimension tables) using foreign

key references.

Latest Answer: A data warehouse design that enhances the

performance of multidimensional queries on traditional relational

databases. One fact table is surrounded by a series of related

tables. Data is joined from one of the points to the center,

providing a so-called ...

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What Snow Flake Schema

Answered by Girinath.S.V.S on 2005-03-17 06:40:48: Snowflake

schemas normalize dimensions to eliminate redundancy. That is,

the dimension data has been grouped into multiple tables instead

of one large

Latest Answer: Any schema with extended dimensions(ie., dimesion

with one or more extensions) is known as snowflake schema ...

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What is a dimension table

Answer posted by Riaz Ahmad on 2005-06-09 14:45:26: A

dimensional table is a collection of hierarchies and categories

along which the user can drill down and drill up. it contains only

the textual attributes.

Latest Answer: A dimensional table contains detail values/data which

is short and wide(ie; less coloums and more rows) Always based

on dimensions analysis is done in Datawarehousing. ...

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What is data mining

Answered by Puneet on 2005-05-07 04:24:28: Data mining is a

process of extracting hidden trends within a datawarehouse. For

example an insurance dataware house can be used to mine data

for the most high

Latest Answer: Data Mining: Smpler way we can define as DWH(Data

Warehouse)+ AI(Artificial Intellegence)used in DSS(Decision

Supportive System) ...

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Tags : Data Mining


What type of Indexing mechanism do we need to use for a typical datawarehouse

Answered by on 2005-03-23 01:45:54: bitmap index

Latest Answer: Space requirements for indexes in a warehouse are

often significantly larger than the space needed to store the data,





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especially for the fact table and particularly if the indexes are

B*trees.Hence, you may want to keep indexing on the fact table

to a ...

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Differences between star and snowflake schemas

Answered by sudhakar on 2005-05-09 18:32:18: star schema

uses denormalized dimension tables,but in case of snowflake

schema it uses normalized dimensions to avoid redundancy...

Latest Answer: star schema uses denormalized dimension tables,but

in case of snowflake schema it uses normalized dimensions to

avoid redundancy... ...

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What is Difference between E-R Modeling and Dimentional Modeling.

Latest Answer: E-R Modeling is a model for OLTP, optimized for

Operational database, namely insert, update, delete data and

stressing on data relational integrity.Dimensional Modeling is a

model for OLAP, optimized for retrieving data because it's

uncommon to update ...

Read Answers (7) | Asked by : Srinu


Why fact table is in normal form?

Latest Answer: The Fact table is central table in Star schema, Fact

table is kept Normalized because its very bigger and so we














should avoid redundant data in it. Thats why we make different

dimensions there by making normalized star schema model

which helps in query ...

Read Answers (7) | Asked by : mallikharjuna reddy


What is junk dimension?what is the difference between junk dimension and

degenerated dimension?

Latest Answer: Junk Dimension also called as garbage dimension. A

garbage dimension is a dimension that consists of low-cardinality

columns such as codes, indicators, status,and flags. The garbage

dimension is also referred to as a junk dimension. Attributes in a

garbage ...

Read Answers (7) | Asked by : ganesh


What are slowly changing dimensions

Latest Answer: The definition of slowly changing dimension is in its

name only. The dimension whichÂ changes slowly with time. A

customer dimension table represents customer. When

creatingÂ a customer, normal assumption is it is independent of

time. But what if address ...

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How do you load the time dimension

Latest Answer: create a procedure to load data into Time Dimension.

The procedure needs to run only once to popullate all the data.














For eg, the code below fills up till 2015. You can modify the code

to suit the feilds in ur table.create or replace procedure ...

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Difference between Snow flake and Star Schema. What are situations where Snow flake

Schema is better

Difference between Snow flake and Star Schema. What are

situations where Snow flake Schema is better than Star Schema

to use and when the opposite is true?

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What is a linked cube?

A cube can be stored on a single analysis server and then defined

as a linked cube on other Analysis servers. End users connected

to any of these analysis servers can then access the cube. This

arrangement

Latest Answer: Hi All,Could you please let me know what is Replicate

Cube & Transparent Cube?Thanks & regards,Amit Sagpariya ...

Read Answers (6) | Asked by : Ramky18


What is the datatype of the surrgate key

Latest Answer: It is a system generated sequence number, an

artificial key used in maintaining history.It comes while handling

slowly changing dimensions ...

Read Answers (6) | Asked by : senthil






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For 80GB Datawarehouse How many records are there in Fact Table There are 25

Dimension and 12 Fact

For 80GB Datawarehouse How many records are there in Fact

Table There are 25 Dimension and 12 Fact Tables

Read Answers (6) | Asked by : srinu


How data in datawarehouse stored after data has been extracted and transformed from

hetrogeneous sources

How data in datawarehouse stored after data has been extracted

and transformed from hetrogeneous sources and where does the

data go from datawarehouse.

Read Answers (6) | Asked by : elektra


What is the role of surrogate keys in data warehouse and how will u generate them?

Latest Answer: A surrogate key is a substitution for the natural

primary key. We tend to use our own Primary keys (surrogate

keys) rather than depend on the primary key that is available in

the source system. When integrating the data, trying to work

with ...

Read Answers (6) | Asked by : venkat


What are the various Reporting tools in the Market





















Answered by Hemakumar on 2005-04-12 05:40:50:

Cognos BusinessObjects MicroStrategies Actuate

Latest Answer: Dear friends you have mentioned so many reporting

tools but missed one open source tool (java based)that is jasper

reportsunfortunatly i am working on that. ...

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What is Normalization, First Normal Form, Second Normal Form , Third Normal

Form

Answer posted by Badri Santhosh on 2005-05-18 09:40:29:

Normalization : The process of decomposing tables to eliminate

data redundancy is called Normalization. 1N.F:- The table should

caontain

Latest Answer: Normalization:It is the process of efficiently organizing

data in a database.There are 2-goals of the normalization

process: 1. Eliminate redundant data 2. Ensure data

dependencies make sense(only storing related data in a

table)First Normal ...

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What does level of Granularity of a fact table signify

Latest Answer: Granularity means nothing but it is a level of

representation of measures and metrics.The lowest level is called

detailed dataand highest level is called summary dataIt depends

of project we extract fact table significanceBye ...

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What are non-additive facts

Latest Answer: Non additive facts are the facts that do not participate

in arithmetic caliculations. for example in stock fact table there

will be opening and closing balances along with qty sold and amt

etc. but opening and closing balances were never used in

arithmetic ...

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What is VLDB

Answered by Kiran on 2005-05-06 20:12:19: The perception of

what constitutes a VLDB continues to grow. A one terabyte

database would normally be considered to be a VLDB.

Latest Answer: Very Large Database (VLDB)it is sometimes used to

describe databases occupying magnetic storage in the terabyte

range and containing billions of table rows. Typically, these are

decision support systems or transaction processing applications

serving large ...

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What is SCD1 , SCD2 , SCD3

Latest Answer: SCD1, SCD2, SCD3 are also called TYPE1, TYPE2,

TYPE3 dimensions Type1: It never maintains history in the target

table. It keeps the most recent updated record in the data base.













Type2: It maintains full history in the target. It maintains history

by ...

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Why are OLTP database designs not generally a good idea for a Data Warehouse

Answer posted by Shri Dana on 2005-04-06 19:04:05: OLTP

cannot store historical information about the organization. It is

used for storing the details of daily transactions while a

datawarehouse is a huge

Latest Answer: OLTP databases are generally volatile in nature which

are not suitable for datawarehouses which we use to store

historic data ...

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What is a CUBE in datawarehousing concept?

Latest Answer: CUBE is used in DWH for representing

multidimensional data logically. Using the cube, it is easy to

carry out certain activity e.g. drill down / drill up, slice and dice,

etc. which enables the business users to understand the trend of

the business. ...

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What is the main differnce between schema in RDBMS and schemas in

DataWarehouse....?














Latest Answer: Diff b.w OLTP and OLAP :------------------------OLTP

Schema :* Normalized * More no.of trans* Less time for queries

execution* More no.of users* Have Insert,delete and update

trans. OLAP (DWH) Schema :* De Normalized * Less no.of

trans* ...

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Tags : RDBMS


What is meant by metadata in context of a Datawarehouse and how it is important?

-

Latest Answer: meta data is stored in repository only not in dataware

house .. but we r placing our repository in database in that way ur

correct ,,but not directly stored in the dataware house plz check it

mam ...

Read Answers (5) | Asked by : Meenal Srivastava

Tags : Metadata


Wht r the data types present in bo?n wht happens if we implement view in the designer

n report

Latest Answer: hi venkateshdimension , measure, detail are objects

type.data types are character, date and numeric ...

Read Answers (5) | Asked by : mayuri


What is the definition of normalized and denormalized view and what are the

differences between them










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What is the definition of normalized and denormalized view and

what are the differences between them

Read Answers (5) | Asked by : sasi


What is the main difference between Inmon and Kimball philosophies of data

warehousing?

Latest Answer: RalfKimball: he follows bottum-up approach i.e., first

create individual Data Marts from the existing sources and then

create Data Warehouse.BillImmon: he follows top-down approach

i.e., first create Data Warehouse from the existing ...

Read Answers (5) | Asked by : MF


Explain degenerated dimension in detail.

Latest Answer: A Degenerate dimension is a Dimension which has

only a single attribute.This dimension is typically represented as

a single field in a fact table.Degenerate Dimensions are the

fastest way to group similar transactions.Degenerate Dimensions

are used when ...

Read Answers (5) | Asked by : sharat


What is the need of surrogate key;why primary key not used as surrogate key

Latest Answer: Datawarehousing depends on the surrogate key not

primary key, for suppose if u r taking the product price it will

change over the time, but product no. will not change but price

will change over the time to maintain the full hystorical data ...














Read Answers (5) | Asked by : rammohan


How do you connect two fact tables ? Is it possible ?

Latest Answer: The only way to connect two fact tables is by using

conformed dimension. ...

Read Answers (5) | Asked by : ssaravalli


Explain the flow of data starting with OLTP to OLAP including staging ,summary

tables,Facts and dimensions.

Explain the flow of data starting with OLTP to OLAP including

staging ,summary tables,Facts and dimensions.

Read Answers (5) | Asked by : madhuom


What are the Different methods of loading Dimension tables

Latest Answer: The answer to this depends on what kind of

Dimension are we loading. If it is not changing , then simply

insert. If it is slowly changing dim of type 1 , update else

insert(50% of the time)Type 2, Only Insert (50% of the time)Type

3 ,Rarely used as we ...

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What are modeling tools available in the Market




















Latest Answer: There is one more data modelling tool available in the

market and that is "KALIDO".This is end to end data warehousing

tool.Â Its a unique and user friendly tool. ...

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What is real time data-warehousing

Latest Answer: Real time Data warehousing means combination of

hetrogenious databases and query and analysis purpose and

Decisionmaking and reporting purpose. ...

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What are Semi-additive and factless facts and in which scenario will you use such kinds

of fact tables

What are Semi-additive and factless facts and in which scenario

will you use such kinds of fact tables

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What is degenerate dimension table?

Latest Answer: Degenerate Dimensions : If a table contains the

values, which r neither dimesion nor measures is called

degenerate dimensions.Ex : invoice id,empno ...

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What is Data warehosuing Hierarchy?




















Latest Answer: hierarchy is an ordered series of related dimension

objects grouped together to perform the multidimensional

analysis.Multidimensional analysis isÂ a technique to modify the

data,so that the dataÂ can be viewed fromÂ different

perspectives and at different ...

Read Answers (4) | Asked by : Venu


What is the difference between view and materialized view

Latest Answer: ViewÂ is a logical reference to a database table. But

Meterial View is actual table and we can refresh data in time

intervels. If you made any change in database table that change

will effect into view but not meterialize view.. ...

Read Answers (4) | Asked by : Aashish Jain


What are the different architecture of datawarehouse

Latest Answer: Architecture 1:Source=>Staging=>DWHArchitecture

2:Source=>Staging=>Datamarts ...

Read Answers (4) | Asked by : stalin.thangaraj


What is hybrid slowly changing dimension

Latest Answer: Hybrid SCDs are combination of both SCDÂ 2 and SCD

3.Whatever changes done in source for each and every record

there is a new entry in target side, whether it may be UPDATE or

INSERT.Â There is new column added to provide the previous

record info (generally ...
















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What is the difference between star schema and snow flake schema ?and when we use

those schema's?

What is the difference between star schema and snow flake

schema ?and when we use those schema's?

Read Answers (4) | Asked by : swarna


Can you convert a snowflake schema in to star schema?

Latest Answer: Star ----->Snow Flake also vice versa is possibleIn Star

SchemaWhen we try to access many attributes or few attributes

from a single dimension table the performance of the query falls.

So we denormalize this dimension table into two or sub

dimensions. ...

Read Answers (4) | Asked by : sainath


Explain the situations where snowflake is better than star schema

Latest Answer: A snowflake schema is a way to handle problems that

do not fit within the star schema. It consists of outrigger tables

which relate to dimensions rather than to the fact table.The

amount of space taken up by dimensions is so small compared to

the ...

Read Answers (4) | Asked by : sainath


















What are Aggregate tables

Latest Answer: Aggregate table contains the summary of existing

warehouse data which is grouped to certain levels of

dimensions.Retrieving the required data from the actual table,

which have millions of records will take more time and also

affects the server ...

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What is a general purpose scheduling tool

Latest Answer: A sheduling tool is a tool which is used to shedule the

datawarehouse jobs...All the jobs which does some process are

sheduled using this tool, which eliminates the manual

intervension. ...

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Which columns go to the fact table and which columns go the dimension table

Answered by Satish on 2005-04-29 08:20:29: The Aggreation or

calculated value colums will go to Fac Tablw and details

information will go to diamensional table.

Latest Answer: Before broken into coloumns is going to the factAfter

broken going to dimensions ...

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Why should you put your data warehouse on a different system than your OLTP system
















Latest Answer: An DW is typically used most often for intensive

querying . Since the primary responsibility of an OLTP system is

to faithfully record on going transactions

(inserts/updates/deletes), these operations will be considerably

slowed down by the heavy querying ...

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What is the main FUNCTIONAL difference between ROLAP,MOLAP,HOLAP?

(NOT AS A RELATIONAL,MULTI, HYBRID?)

Latest Answer: The FUNCTIONAL difference between these is how

they information is stored. In all cases, the users see the data as

a cube of dimensions and facts.ROLAP - detailed data is stored in

a relational database in 3NF, star, or snowflake form. Queries ...

Read Answers (3) | Asked by : purna chowdary


Is it correct/feasible develop a Data Mart using an ODS?

the ODS is technically designed to be used as the feeder for the

DW and other DM's -- yes. It is to be the source of truth.Read the

complete thread at http://asktom.oracle.com/pls/ask/f?

p=4950:8:16165205144590546310::NO::F4950_P8_DISPLAYID,F4

950_P8_CRITERIA:30801968442845,

Latest Answer: Hi According to Bill Inmon's paradigm an enterprize

can have one datware house and datamarts source their

information from the datawarehouse. In the dataware house,

information is stroed in 3rd Normalization. This Dataware house is

build on ODS. You ...











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What are the possible data marts in Retail sales.?

Latest Answer: product informationstore time ...

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What is BUS Schema?

Latest Answer: Bus Schema : Let we consider/explain these in x,y

axis Dimension Table : A,B,C,D,E,F ...

Read Answers (3) | Asked by : Reddeppa


What are the steps to build the datawarehouse

Latest Answer: 1.Understand the bussiness requirements.2.Once the

business requirements are clear then Identify the

Grains(Levels).3.Grains are defined ,design the Dimensional

tables with the Lower level Grains.4.Once the Dimensions are

designed,design the Fact table ...

Read Answers (3) | Asked by : stalin


What is rapidly changing dimension?

Latest Answer: A rapidly changing dimension is a result of poor

decisions during the requirements analysis and data modeling

stages of the Data Warehousing project. If the data in the


















dimension table is changing a lot, it is a hint that the design

should be revisited. ...

Read Answers (3) | Asked by : Deeprekha


What is data cleaning? how is it done?

Latest Answer: it is a process of identifing and changing the

inconsistencies and inaccuracies ...

Read Answers (3) | Asked by : sahira2000


Do u need seperate space for Datawarehouse & Data mart

Latest Answer: I think the comments made earlier are not specific.We

dont required any seperate space for data mart and data where

house unless until those marts are too big or client required.We

can maintain both in a same schema. ...

Read Answers (3) | Asked by : chramgopal


What is source qualifier?

Latest Answer: Source qualifier is a transformation which extracts

data from the source. Source qualifier acts as SQL query when

the source is a relational database and it acts as a data

interpreter if the source is a flatfile. ...

Read Answers (3) | Asked by : spavate






















Explain ODS and ODS types.

Latest Answer: It is designed to support Operational Monitoring. It is

subject oriented,integrated database which holds the

current,detailed data.data here is volatile ...

Read Answers (3) | Asked by : chetan


What is a level of Granularity of a fact table

Latest Answer: It also means that we can have (for example) data

agregated for a year for a given product as well as the data can

be drilled down to Monthly, weekl and daily basis...teh lowest

level is known as the grain. going down to details is Granularity ...

Read Answers (2)


How are the Dimension tables designed

Latest Answer: Find where data for this dimension are

located. Figure out how to extract this data. Determine how to

maintain changes to this dimension (see more on this in the next

section). Change fact table and DW population routines. ...

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1.what is incremental loading?2.what is batch processing?3.what is cross reference

table?4.what is aggregate

1.what is incremental loading?2.what is batch processing?3.what

is cross reference table?4.what is aggregate fact table

Read Answers (2) | Asked by : usha


















Give examples of degenerated dimensions

Latest Answer: Degenerated Dimension is a dimension key without

corresponding dimension. Example: In the PointOfSale

Transaction Fact table, we have: Date Key (FK), Product Key

(FK), Store ...

Read Answers (2) | Asked by : stalin


What is the difference between Datawarehouse and Datawarehousing

Latest Answer: dataware house is a container to store the historical

datawhere as dataware hosuning is a process or technique to

analyze tha data in the ware house ...

Read Answers (2) | Asked by : shivaleela


Summarize the differene between OLTP,ODS AND DATA WAREHOUSE ?

Latest Answer: ODS: this is operational data stores, which means the

real time transactional databases. In data warehouse, we extract

the data from ODS, transform in the stagging area and load into

the target data warehouse.I think, earlier comments on the ODS

is little ...

Read Answers (2) | Asked by : thumatinagaraju


What is the purpose of "Factless Fact Table"? How it is involved in Many to many

relationship?




















What is the purpose of "Factless Fact Table"? How it is involved in

Many to many relationship?

Read Answers (2) | Asked by : abhijit.joshi


What is the difference between Data modelling and Dimensional modelling?

Latest Answer: Dimensional Modelling is the Analysis of the

Transactional Data (Facts) based on Master Data

(Dimensions).Data Modeling is the process of creating a data

model by applying a data model theory to create a data model

instance.Regards,Sridhar Tirukovela ...

Read Answers (2) | Asked by : Saravanan


Explain the advanatages of RAID 1, 1/0, and 5. What type of RAID setup would you put

your TX logs

Latest Answer: Raid 0 - Make several physical hard drives look like

one hard drive. No redundancy but very fast. May use for

temporary spaces where loss of the files will not result in loss of

committed data. Raid 1- Mirroring. Each hard drive in the ...

Read Answers (1)


What is the life cycle of data warehouse projects

Latest Answer: STRAGEGY & PROJECT PLANNINGDefinition of scope,

goals, objectives & purpose, and expectationsEstablishment of

implementation strategyPreliminary identification of project
















resourcesAssembling of project teamEstimation of project

scheduleREQUIREMENTS ...

Read Answers (1) | Asked by : raki2kaki


What is slicing and dicing? Explain with real time usage and business reasons of it's use

Latest Answer: Hi, Slicing and Dicing is a feature that helps us in

seeing the more detailed information about a particular thing. For

eg: You have a report which shows the quarterly based

performance of a particular product. But you want to see it ...

Read Answers (1) | Asked by : Sheen


What is meant by Aggregate Factable?

Factable having aggregated calculations like sum, avg, sum(sal)

+sum(comm),these are Aggregated FactableCheersPadhu

Latest Answer: An aggregate fact table stores information that has

been aggregated, or summarized from a detail fact table.

Aggregate fact table ares useful in improving query

performance. Often an aggregate fact table can be maintained

through the use of ...

Read Answers (1) | Asked by : padmanathan


What is difference between BO, Microstrategy and Cognos

Latest Answer: BO is a ROLAP Tool,Cognos is a MLAP Tool and

MicroStrategy is a HLAP Tool ...

Read Answers (1) | Asked by : prasad


















What is data validation strategies for data mart validation after loading process

Latest Answer: Data validation is to make sure that the loaded data is

accurate and meets the business requriments.Strategies are

different methods followed to meet the validation requriments ...

Read Answers (1) | Asked by : PREM NARAYAN SAINI


Which automation tool is used in data warehouse testing?

Latest Answer: No Tool testing in done in DWH, only manual testing

is done. ...

Read Answers (1) | Asked by : Chaitra Bharadwaj


What are the advantages data mining over traditional approaches?

Latest Answer: Data Mining is used for the estimation of future. For

example, if we take a company/business organization, by using

the concept of Data Mining, we can predict the future of business

interms of Revenue (or) Employees (or) Cutomers (or) Orders ...

Read Answers (1) | Asked by : Rohit Gupta

Tags : Data Mining


What is the differences between the static and dynamic caches?

Latest Answer: static cache stores overloaded values in the memory

and it wont change throught the running of the session where as




http://www.geekinterview.com/tags/data-mining/














dynamic cache stores the values in the memory and changes

dynamically duirng the running of the session used in scd types --

where target ...

Read Answers (1) | Asked by : jyothi


What is cube and why we are crating a cube what is diff between etl and olap cubes any

budy ans

What is cube and why we are crating a cube what is diff between

etl and olap cubes any budy ans plz?

Read Answers (1) | Asked by : thumati nagaraju


What are the various attributes in time dimension, If this dimension has to consider

only date of birth

What are the various attributes in time dimension, If this

dimension has to consider only date of birth of a citizen of a

country?

Read Answers (1) | Asked by : naag


What are late arriving Facts and late arriving dim ? How does it impacts DW?

Latest Answer: Late arriving Fact table:Â Â Â Â Â Â Â This is rarely

happens in practice. For example there was a credit card of HDFC

transaction happened on 25th Mar 2005, but this record we

received on 14th Aug 2007. During this period there is a

possibility of change ...

Read Answers (1) | Asked by : Navin

















What are the various techniques in ER modelling?

Latest Answer: ER modelling is the first step for any Database project

like Oracle, DB2.1. Conceptual Modelling2. Logical Modelling3.

Physical Modelling ...

Read Answers (1) | Asked by : bharat


Explain Bill Inmon's versus Ralph Kimball's Approach to Data Warehousing.

Bill Inmon vs Ralph Kimball In the data warehousing field, we

often hear about discussions on where a person / organization's

philosophy falls into Bill Inmon's camp or into Ralph Kimball's

Latest Answer: Bill inmon : Data warehouse à Data martRalph Kimbol

: Data mart à Data warehouseCheers,Sithu,

[email protected] ...

Read Answers (1) | Asked by : Pranay


I want to know how to protect my data over networ.which software will be use

View Question | Asked by : chandra


Information Packages(IP) are advanced by some author as a way of building

dimensional models - e.g.

Information Packages(IP) are advanced by some author as a way

of building dimensional models - e.g. star schemas. Explain what




















IPs are and Give an example of it\'s use in building a dimensional

model.

View Question | Asked by : Rokeya Begum


What is Replicate,Transparent and Linked cubes?

View Question | Asked by : navsa


What is meany by survey and extraction tables in DW?

View Question | Asked by : stalin


What is the business rule for writing the requirement?

View Question | Asked by : Gunnampalli


How do you load the data conditionally by run steps ?

View Question | Asked by : ada





















DWH BASICS Interview Questions

Documents

cross reference

building dimensional

rapidly changing

snow flake

olap including

multiple fact

factless fact

denormalized