Avoid duplicating the work of a database server: Instruct DB2 to filter and process data according to your needs rather than doing this work in your application.
避免重复数据库服务器的工作:指示DB 2根据您的需要过滤和处理数据,而不是在应用程序中做这项工作。
2
To avoid duplicating that process, XPath provides a method called compile , which simply takes your string XPath expression as its only argument.