Differences between OLTP and OLAP

Online transaction processing system:
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  1. In OLTP system, the tables are in normalized structure
  2. As the OLTP is in normalized structure, DML operations like Updates and deletes will be faster
  3. Simple queries are run against the OLTP system
  4. OLTP system contains only current data. As the OLTP system does not contain history data, it cannot be used in reporting 

Online analytic processing system:
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  1. In OLAP system, the tables are in de normalized structure
  2.  As the OLAP is in de normalized structure, the numbers of joins between tables are less and hence select statements will be faster
  3.  Complex queries are run against the OLAP system
  4.  OLTP system contains only history data and can be used for reporting purpose

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