difference between multi relational OLAP & multidimensional
OLAP

Answer Posted / suresh

Sr Relational Modelling Multi-Dimensional Modelling
1 Relational models can be very complex with hundreds
of tables having long chains of relationship among them.
Multidimensional modeling are very simple. Each of
the dimension table has a direct relationship with the fact
table
2 Normal data modeling is quite flexible. The
Multidimensional modeling has a rigid structure
3 One of the goals of relational modeling is to
confirm to the rules of normalization. In a normalized
database each data value is stored only once.
Multidimensional modeling are radically
denormalized. The dimension tables have a high number of
repeated values in their fields.
4 Standard relational models are optimized for On
Line Transaction Processing. OLTP needs the ability to
efficiently update data. This is provided in a normalized
database that has each value stored only once.
Multidimensional modeling are optimized for On Line
Analytical Processing. OLAP needs the ability to retrieve
data efficiently. Efficient data retrieval requires a
minimum number of joins. This is provided with the simple
structure of relationship in a Multidimensional modeling,
where each dimension table is only a single join away from
the fact table.
5 SQL queries required to manipulate relational data
MDX queries required to manipulate multi-
dimensional data
6 Tables are units of relational data storage.
Cubes are units of multi-dimensional data storage.
7 Table fields of particular data type store the
actual data. Dimensions and measures stores actual data.
8 Table size is measured in number of record set.
Cube size is measured in number of Cellsets. In
this sense, MS Excel Pivot Table can accommodate 2,040,000
cellsets (8000 * 255). Considering the summary data to be
reported, this is reasonably large. Pivot Table can report
at the most 8000 different items.

Is This Answer Correct ?    10 Yes 4 No



Post New Answer       View All Answers


Please Help Members By Posting Answers For Below Questions

anyone send me aptitude and technical placement paper of Hewitt

1379


What type of questions are asked in interview?

1269


difference between w2k and win xp....

1369


hey,,,hi have taken an emergency date of 21st july...i was continuously checking for dates n i was not able to get a normal date n my school is starting from 8th of september...so plz tell me can i get a rejection based on this, that i have taken an emergency date?????

1359


HOW WE CAN CORRELATE THE MA\ECHANICAL POWER TO ELECTRICAL POWER. SUPPOSE IF I WANT A PUMP OF PUMPIG 200 LPM AT 20 METER HEAD MENAS WHAT IS THE POWER NEEDED FOR PUMP IN ELECTRCAL AND HOW CAN WE GET IT

1398






synchronous and asynchronous transmission

1484


Modal vs Modaless in VB??

1509


how is the config take place and from reciever side how will process the data into internal table

1329


when did actually oil exploration start

1444


what is the proper location of sample point for sphere tank?

1557


what is the differences between DTD's and XML schema?

1538


sir i have 4 year gap in engineering. i would complete my degree b.tech it in 2014. it will be may be in 2nd class.my hsc is also with 2nd class. i am week in programming. Then if i want highest package upto 5-6 lacs then what should i prepare myself as a good engineer to get this package???

1421


which topics are come from quizs

1215


15. What is your Future Plans for the Company if Permanently Employed?

3373


can anybody send me the technical papers of hewitt associates pls...I cleared aps n GD n has only less time for technical round?

1766