OLTP and OLAP activities are quite different from their aims and their data access requirements:

• OLTP activities provide a detail audit of single events in the observed system, while OLAP gives a picture of the system as a whole.
• OLTP tracks the changes caused by these events and supports the resulting operations on the database while OLAP supports analytical processes of a database.
• OLTP needs detailed information of the observed entities, which are not relevant for analysis. OLAP mainly requires aggregate data of a group of entities.
• OLTP requires high performance to spot single datasets in the database, while OLAP needs high performance when evaluating groups of datasets or all datasets.
• OLTP systems function best on relational database systems, while OLAP systems function best with multi dimensional database systems (although there also exist relational and hybrid OLAP systems)
• The typical query in an OLTP environment is asking the database for specific information like the name of a person, while OLAP systems ask for frequencies, averages or sums within groups, like the number of people living in a town.