它如何选择在优化存取路径中使用这些策略中的哪一个？
How does it choose which of these strategies to use in the optimized access paths?
尽管DB 2优化器对选择最佳访问路径有所帮助，但结果还是依赖于输入数据，优化器无法访问或控制这些数据。
Although the DB2 optimizer is helpful for selecting the best access path, the result depends on the input data, which is often not accessed or controlled by the optimizer.
还有，在选择访问路径之前，优化器首先会执行一系列查询转换以增加可用访问路径的数目。
Also, before selecting the access path, the optimizer first performs a series of query transformations to increase the number of access paths available.
应用推荐