olap:online analytical processing is that which describes procesing at warehouses.

oltp:online transactional processing is that which describes at the operational sites..

oltp olap

1.Mb-tb of data 1.gb-tb of data

2.mostly updates 2.mostly reads

3.many small transactions 3.summerized and consolidated data

4.raw data which is updated frequently 4.users are decision makers and analyts

5.consistency recoverability is critical

6.clerical users