Commercial databases compete for market share, which is composed of not only net-new sales to those purchasing a database for the first time, but also competitive "win-backs" and migrations. Database migration, or the act of moving both application code and its underlying database platform from one database to another, presents a serious administrative and application development challenge fraught with large manual costs. Migration is typically a high cost effort due to incompatibilities between database platforms. Incompatibilities are caused most often by product specific extensions to language support, procedural logic, DDL, and administrative interfaces. The migration evaluation is the first step in any competitive database migration process. Historically this has been a manual process, with the high costs and subjective results. This has led us to reexamine traditional practices and explore an automatic, innovative solution. We have designed and implemented the Migration Evaluation and Enablement Tool for DB2 for Linux Unix and Windows, or MEET DB2, a tool for automatically evaluating database migration projects. Encapsulated in a simple one-click interface, MEET DB2 is able to provide detailed evaluation of migration complexity based on its deep analysis on the source database. In this paper, we present MEET DB2, and discuss many aspects of our design, and report measurements from real-world use cases. In particular, we show a novel way to use XML and XQuery in this domain for better extensibility and interoperability. We have evaluated MEET DB2 on 18 source code samples, covering nearly 1 million lines of code. The utility has provided benefits in several dimensions including: dramatically reduced time for evaluation, consistency, improved accuracy over human analysis, improved reporting, reduced skill requirements for migration analysis, and clear analytics for product planning.

A coherent radar on a cliff overlooking the ocean was used to illuminate the ocean surface at a grazing angle of 10/spl deg/ during and after the passage of a ship through the beam. Simultaneous L-band and X-band data were collected. The display of surface reflectivity (power) showed a prominent narrow-vee feature at L-band, as was observed in earlier L-band satellite observations. A corresponding narrow-vee structure was observed in X-band, but was not as strong as other components of the wake signature. On the other hand, the Doppler-velocity displays at both radar frequencies yielded the same distinctive signature, i.e., a pair of compact features traveling outward from the centerline, each exhibiting a Doppler velocity that was the Bragg phase velocity corresponding to that radar frequency. The location of the velocity signature coincided at L-band with that of the power signature. Further, the L-band wake was persistent enough to verify that the feature was propagating at the Bragg group velocity, roughly the same as that for X-band. This result confirms an earlier hypothesis that the mechanism underlying the narrow-vee signature is the outward propagation of Bragg waves created by the ship's passage.