MOLAP, ROLAP, HOLAP are terms you will come across in SSAS .
Keeping it simple what they mean are :
MOLAP is Multidimensional OLAP : what ever aggregations, group by etc you can imagine on the query to generate the counts are pre-aggregated & calculated before hand in cube , so that the execution is fast & don't have to calculate when a request is made.
ROLAP is Relational OLAP : when ever a query is issued , they will be executed against the relational databases to return the resultset. you can imagine this as a stored procedure call.
HOLAP is Hybrid OLAP : It is a Hybrid of above two, HOLAP is used where aggregations, group by etc are used to return the result set & MOLAP is used for regular queries. Sharepoint deployment of reports built on SSAS cubes & SSRS reports mostly use HOLAP. MOLAP for main repots & HOLAP for drill down reports.
Keeping it simple what they mean are :
MOLAP is Multidimensional OLAP : what ever aggregations, group by etc you can imagine on the query to generate the counts are pre-aggregated & calculated before hand in cube , so that the execution is fast & don't have to calculate when a request is made.
ROLAP is Relational OLAP : when ever a query is issued , they will be executed against the relational databases to return the resultset. you can imagine this as a stored procedure call.
HOLAP is Hybrid OLAP : It is a Hybrid of above two, HOLAP is used where aggregations, group by etc are used to return the result set & MOLAP is used for regular queries. Sharepoint deployment of reports built on SSAS cubes & SSRS reports mostly use HOLAP. MOLAP for main repots & HOLAP for drill down reports.
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