A classic, albeit a bit dated, book is Fast Track to MDX. It’s a great overview and a quick read, though it doesn’t cover the new MDX features of SQL Server 2005. The Spofford book MDX Solutions is more up date and a little deeper, but a bit harder to get through. I also highly … Read more
There are a number of data warehousing software vendors that are based on Postgresql (and contribute OLAP related changes back to core fairly regularly). Check out https://greenplum.org/. You’ll find that PG works a lot better (for nearly any workload, OLAP especially) than MySQL. Greenplum and other similar solutions should work a bit better than PG … Read more
Might be the case mondrian.rolap.aggregates.Read is set to true and mondrian.rolap.aggregates.Use is set to false. Please set mondrian.rolap.aggregates.Use=true and check. Reference: http://mondrian.pentaho.com/documentation/configuration.php If this is not the case, please attach all the properties related to aggregate tables and the complete cube definition XML.
Mythology I always thought that databases should be denormalized for reading, as it is done for OLAP database design, and not exaggerated much further 3NF for OLTP design. There’s a myth to that effect. In the Relational Database context, I have re-implemented six very large so-called “de-normalised” “databases”; and executed over eighty assignments correcting problems … Read more
A data warehouse is a database with a design that makes analyzing data easier† and faster, often with data from multiple sources. It usually has a dimensional model, meaning fact tables and dimension tables. OLAP is a set of operations that one can do on a data set, such as pivoting, slicing, dicing, drilling. For … Read more
Here you will find a better solution OLTP vs. OLAP OLTP (On-line Transaction Processing) is involved in the operation of a particular system. OLTP is characterized by a large number of short on-line transactions (INSERT, UPDATE, DELETE). The main emphasis for OLTP systems is put on very fast query processing, maintaining data integrity in multi-access … Read more