In 1998, Microsoft released OLAP Services as their first foray into competing with Essbase. It was enough to scare Arbor into merging with Hyperion, because they feared Essbase would turn into a commodity since Microsoft was now basically giving away “OLAP” with SQL Server. But it wasn’t until 2000 when Microsoft released Analysis Services that they had a product that even began to compete with Essbase.
Why is this the 4th most major event of the decade? Because it led to Hyperion taking its focus off Essbase (how could you compete with something free?) and moving its attentions to building applications that Microsoft didn’t have. The good news is that while Microsoft had a good run in the last millennium, companies now know that you buy the best product not the one with the Microsoft name. Like Microsoft lost the search wars, they lost the OLAP wars to Essbase, Cognos, and Business Objects. Simply put, companies would rather pay for a better product than use a free one. Essbase never became a commodity (despite Hyperion’s own attempts to marginalize it by renaming it Hyperion System 9 BI+ Analytic Services) and under Oracle’s leadership, it’s a flagship product again.