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Flashcards in Dimensional Data modelling Deck (31):
1

The process of organizing and preparing data for analysis is called as

data staging

2

which of these ensures data becomes consistent, relevant and free from ambiguities
a)data provisioning
b)data gathering
c)data staging

c)data staging

3

defining data and their relationships are called

data modeling

4

data warehouse has ________tables

denormalized

5

The tables in DW are ______-only

read-only hence normalization not required

6

DB architecture with summarised, harmonized, cleansed, consolidated data is called

data warehouse

7

operational data --txn data are both one and the same

T/F

T

8

Detailed view of the fact table is called

dimensional table

9

Number of dimension in star schema is fixed
T/F

F depends on analytics requirements

10

Why is star schema called multidimensional structure

number of dimesnions is not fixed

11

Default numnber of dimensions in star schema is

3

12

fact table contans ________& _______data

txn and organizational data

13

the fact table contains txn attributes also called as

key /measures

14

detailed view of fact is called

dimensional tables

15

fact table has separate currency unit as attribute T/F

T. to store key measures in different currenncies

16

data in __-table without data in __ table is not useful

fact , dimension

17

data package dimension contains

details when txn is loaded in to fact table
time stamp ,loadingnumber

18

data in __-table without data in __ table is not useful

fact, dimension

19

data package dimension contains

details when txn is loaded into fact table
time stamp, loading number

20

IS DATA DIMENSION PACKAGE USED FOR ANALYTICS

NO..simply used for maintenance ,keep a check rogue loads

21

IS DATA DIMENSION PACKAGE USED FOR ANALYTICS

NO..simply used for maintenance, keep a check rogue loads

22

UOM and currency key is in text

us dollars, kilograms lbs etc

23

the rogue load concept is with respect to the fact table
t/f

t

24

_ TO _ relational between dimension and fact table

1: M

25

adv of star schema

simple: 1 fact table many dimensions tab
only 1 join easy query

26

disadvantages of star schema

country state zip problem
alphanumeric foreign key --slower
does not support multiple languages

27

HISTORIZATION

history showing changes in attribute

28

does star schema support historization

No

29

Hierarchy in dimension table causes

anomalies.especially when we have 2 hierarchies

30

___________- anomaly is caused due to hierarchy

update

31

which layer in data warehouse has read optimise data cube for querying

reporting layer