Here are some interesting technologies at least from my perspective.
JPivot is a JSP custom tag library that renders an OLAP table and let users perform typical OLAP navigations like slice and dice, drill down and roll up. It uses Mondrian as its OLAP Server.
Mondrian is an OLAP server written in Java. It enables you to interactively analyze very large datasets stored in SQL databases without writing SQL.
Mondrian 3.0 includes olap4j 0.9.6 along with significant improvements to security and additional function support. Highlights of this release include:
olap4j API — an Open Java API for OLAP Rollup policy enhancements Aggregate role support Support for aggregation of distinct-count measures Improved dimension sharing Over 50 new scalar functions JNDI support
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