There are a lot of points to consider about the acquisition, but the demise of MySQL is not one of them, at least not for the reasons that you mentioned. The two databases target vastly different markets. In other words, if MySQL had vanished from existence last week, Oracle would be making no extra sales this week. I don't know if their strategy is to grab mindshare in the web world, or try to develop an upgrade path for LAMP developers moving into the enterprise world, but I don't think it's the expensive purchase and subsequent abandonment of MySQL. Most likely they are trying to get a foothold for some hopefully tactical future benefit, or simply promote their brand in new markets like Microsoft with SQL Server Express.