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sqldata-warehouseolap

Datawarehouse and OLAP, ROLAP

I have read all those article about datawarehouse and olap.....however I have some question on it

  1. I have created a datawarehouse using mysql and I also created an API which contain ad-hoc query to query from the datawarehouse, so is this API consider as ROLAP?
  2. Is it possible to create own OLAP? If yes, how?
Solution

  • Usually data warehouse has normalized structure and DWH is not the same as ROLAP.

    ROLAP it is technique used to modeling data. ROLAP is usually used for reporting. ROLAP is very good to make analytical query and you can use many reporting (BI) tools to easily build reports on you data.

    It isn't necessary to write you own application to build reports. ROLAP (relational OLAP) it is when you model you data as "star" or "snowflake" using facts and dimension tables in traditional RDBMS. It star schemas also called "multidimensional cubes".

    By OLAP often is meant MOLAP (multidimensional OLAP) - it's when you really store your data in multidimensional data structure in special data stores (not in RDBMS).

    You shouldent create you own MOLAP e data storag- you should use alredy developed OLAP servers like MANDARIN, Pentaho Olap,Essbase, ORACLE EE database with OLAP option.