Upload
johnny-leung
View
217
Download
2
Embed Size (px)
Citation preview
OnLine Analytical Processing
Seminar Presentation By
IQxplorer
Under the guidance of Mr. Indraneel Mukhopadhyay
What is OLAP
OnLine Analytical Processing ia a technology that uses multidimensional view of aggregate data for quicker access to strategic information.
How OLAP Helps
It helps in decision making, business modeling, and operations research activities by transforming raw Data warehouse data into strategic information
Four Main Characteristics of OLAP–Use multidimensional data analysis techniques–Provide advanced database support–Provide easy-to-use end user interfaces–Support client/server architecture
Multidimensional Data Analysis Techniques
–The processing of data in which data are viewed as part of a multidimensional structure.
–Multidimensional view allows end users to consolidate or aggregate data at different levels.
Multidimensional Data AnalysisRelational databases contains lists of records whose information is organised into fields and is based on a row and column data format(one dimensional).
However some relational tables where there is more than a one-to-one relationship between the fields lends itself to multidiensional represtation.
Product Region SalesNuts East 50
Nuts West 60
Nuts Central 100
Bolts East 90
Bolts West 120
Bolts Central 140
Screws East 40
Screws West 70
Screws Central 80
Washers East 20
Washers West 10
Washers Central 30
Single Dimensional View
East West CentralNuts 50 60 100Bolts 90 120 140Screws 40 70 80Washers 20 10 30
Multidimensional View
OLAP Architecture–Three Main Modules
OLAP Graphical User Interface (GUI)OLAP Analytical Processing LogicOLAP Data Processing Logic
–OLAP systems are designed to use both operational and Data Warehouse data.
OLAP Server Arrangement
OLAP Server With Multidimensional Data Store Arrangement
Relational OLAPRelational On-Line Analytical Processing (ROLAP) provides OLAP functionality by using relational database and familiar relational query tools.Extensions to RDBMS
Multidimensional data schema support within the RDBMSData access language and query performance optimized for multidimensional data
Support for very large databases
Multidimensional Data Schema Support within the RDBMS
Normalization of tables in relational technology is seen as a stumbling block to its use in OLAP systems.DSS data tend to be non-normalized, duplicated, and pre-aggregated.ROLAP uses a special design technique to enable RDBMS technology to support multidimensional data representations, known as star schema.Star schema creates the near equivalent of a multidimensional database schema from the existing relational database
A Typical ROLAP Client/Server Architecture
The real limitation of OLAP databases is almost always the number of cells and not the number of dimensions.As the number of dimensions increases the number of cells increases expotentially so a 16 dimension database with 5 members in each has 152 billion cells.Most OLAP servers reach their limit in cell numbers before they hit their dimensions limit
LIMITATIONS
CONCLUSIONIn essence OLAP technology is fast, flexible data summarisation and analysis.
OLAP servers are a superior technology for Business Intellgence applications.
OLAP servers and relational databases can work in harmony to create an environment that delivers data quickly to perform the analysis needed to make the best business decisions.