Transcript CH-20 Information Integration

CH-20 Information
Integration
Continued……
On-Line Analytic Processing (OLAP)
• OLAP is used to query very large amount of data in the data warehouse of
company
• It involves highly complex queries that use one or more aggregators
• OLAP queries are also called as decision support queries
• common database operation touch very small amount of data and they are
referred as OLTP (online transaction processing)
• OLAP queries are considered as long transactions and long transactions
locking the entire database would shutdown the ordinary OLTP transactions so
OLAP data is stored separately in data warehouse rather then in ordinary
database
Multidimensional View Of OLAP Data
Star Schemas
Slicing and Dicing
Thank You !